The town was ancient, beautiful, and at any other time Pitt would have found it interesting. Were he here on holiday with his family, he would have loved to explore the medieval streets and alleys, and learn more of its history, which was peculiarly dramatic.

As it was, he had the strong feeling that he and Gower were wasting time. They had watched Frobisher’s house for well over a week, and seen nothing that led them any closer to whatever Wrexham had killed West to prevent him from telling Special Branch. Visitors came and went; not only men but women also. Neither Pieter Linsky nor Jacob Meister had come again, but there had been dinner parties where at least a dozen people were present. Delivery men had come with baskets of the shellfish for which the area was famous. Scores of oysters had come, shrimps and larger crustaceans like lobsters, and bags of mussels. But then the same could be said of any of the other larger houses in the area.

Gower wandered along the same path, his face sunburned, his hair flopping forward. He stopped just inside the wall, a yard or two short of Pitt. He too leaned against the ledge as if he were watching the sailing boat.

‘Where did he go?’ Pitt asked quietly, without looking at him.

‘Only to the same café as usual,’ Gower answered, referring to Wrexham, whom one or the other of them had followed every day. ‘I didn’t go in because I was afraid he’d notice me. But I saw the same thin man with the moustache go in, then came back out again in about half an hour.’

There was a slight lift in his voice, a quickening. ‘I watched them through the open window for a few minutes as if I were waiting for someone. They were talking about more people coming, quite a lot of them. They seemed to be ticking them off, as if from a list. They’re definitely planning something.’

Pitt would like to have felt the same stir of excitement, but all the time he’d been observing, events seemed both too careful and too half-hearted for the passion that inspires great political change. He and Narraway had studied revolutionaries, anarchists, firebrands of all beliefs, and this had a cautious feel to it, the safe talking about it of those who do not actually want to take risks. Gower was young. Perhaps he attributed to them some of the enthusiasm he still felt himself. And he did feel it. Pitt smiled as he thought of Gower laughing with their landlady, complimenting her on the food and letting her explain to him how it was cooked. Then he told her about such English favourites as steak and kidney pudding, plum duff, and pickled eels. She had no idea whether to believe him or not.

‘They’ve delivered more oysters,’ Pitt remarked. ‘It’s probably another party. Whatever Frobisher’s political beliefs about changing conditions for the poor, he certainly doesn’t believe in starving himself, or his guests.’

‘He would hardly go around letting everyone know his plans . . . sir,’ Gower replied quickly. ‘If everyone thinks he’s a rich man entertaining his friends in harmless idealism he never intends to act on, then nobody will take him seriously. That’s probably the best safety he could have.’

Pitt thought about it for a while. What Gower said was undoubtedly true, and yet Pitt was uneasy about it. The conviction that they were wasting time settled more heavily upon him, yet he could find no argument that was pure reason rather than a niggling instinct born of experience.

‘And all the others who keep coming and going?’ he asked, at last turning and facing Gower, who was unconsciously smiling as the light warmed his face. Below him in the small square a woman in a fashionable dress, wide-sleeved and full-skirted, walked from one side to the other and disappeared along the narrow alley to the west. Gower watched her all the way, nodding very gently in approval.

Gower turned to Pitt, his fair face puzzled. ‘Yes, about a dozen of them. Do you think they’re really harmless, sir? Apart from Wrexham, of course?’

‘Are they all wild revolutionaries pretending very successfully to be ordinary citizens living satisfied and rather pedestrian lives?’ Pitt pressed.

It was a long time before Gower answered, as if he were weighing his words with intense care. He turned and leaned on the wall, staring at the water. ‘Wrexham killed West for a reason,’ he said slowly. ‘He was in no present danger, except being exposed as an anarchist, or whatever he would call himself. Perhaps he doesn’t want chaos, but a specific order that he considers fairer, more equal to all people. Or it may be a radical reform he’s after. Exactly what it is the socialists want is one of the things we need to learn. There may be dozens of different goals—’

‘There are,’ Pitt interrupted. ‘What they have in common is that they are not prepared to wait for reform by consent; they want to force it on people, violently, if necessary.’

‘And how long will they have to wait for anyone to hand it over voluntarily?’ Gower said with an edge of sarcasm. ‘Whoever gave up power if they weren’t forced to?’

Pitt scanned his memory for the history he could recall. ‘None that I can think of,’ he admitted. ‘That’s why it usually takes a while. But the abolition of slavery was passed through Parliament without overt violence. Certainly without revolution.’

‘I’m not sure the slaves would agree with that assessment,’ Gower said with a twist of bitterness. ‘Perhaps we’re looking at a would-be Wilberforce?’

Pitt looked at him obliquely, slightly ashamed of his shallow remark about slavery.

‘It’s time we found out what we are looking at,’ he conceded.

Gower straightened up. ‘If we ask open questions it’s bound to get back to Frobisher, and he may take a great deal more care. The one advantage we have, sir, is that he doesn’t know we’re watching him. Can we afford to lose that?’ He looked anxious, his fair brows drawn together in a frown, the sunburn flushing his cheeks.

‘I’ve been making a few enquiries,’ Pitt said.

‘Already?’ Suddenly there was an edge of anger in Gower’s voice.

Pitt was surprised. It seemed Gower’s easy manner hid an emotional commitment he had not seen. He should have. They had worked together for over two months even before the hectic chase that had brought them here.

‘As to who I can ask for information without it being obvious,’ he replied levelly.

‘Who?’ Gower said quickly.

‘A man named John McIver. He’s another expatriate Englishman who’s lived here for twenty years. Married to a French woman.’

‘Are you positive he’s trustworthy, sir?’ Gower was still sceptical. ‘It’ll take only one careless word, one remark made idly, and Frobisher will know he’s being watched. We could lose the big ones, the people like Linsky, and Meister.’

‘I didn’t choose him blindly,’ Pitt replied. He did not intend to tell Gower that he had encountered McIver before, on a quite different case.

Gower drew in his breath, and then let it out again. ‘Yes, sir. I’ll stay here and watch Wrexham, and whoever he meets with.’ Then he flashed a sudden, bright smile. ‘I might even go down into the square and see the pretty girl with the pink dress again, and drink a glass of wine.’

Pitt shook his head, feeling the tension ease away. ‘I think you’ll do better than I will,’ he said ruefully.

‘Of course I miss London, but don’t misunderstand me, sir,’ he said, leaning back in his garden chair in the sun. He had offered Pitt wine and little sweet biscuits, and – when he declined those – fresh crusty bread and a soft country cream cheese, which he accepted with alacrity.

Pitt waited for him to continue.

‘I love it here,’ McIver went on. ‘The French are possibly the most civilised nation on earth – apart from the Italians, of course. Really know how to live, and do it with a certain flair that gives even mundane things a degree of elegance. But there are parts of English life that I miss. Haven’t had a decent marmalade in years. Sharp, aromatic, almost bitter.’ He sighed, a smile of memory on his face. ‘The morning’s Times, a good cup of tea, and a manservant who is completely unflappable. I used to have a fellow who could have announced the Angel of Doom with the same calm, rather mournful air that he announced the Duchess of Malmsbury.’

Pitt smiled, and ate a whole slice of bread and sipped his wine before he pursued the reason he had come.

‘I need to make some very discreet enquiries: government, you understand?’

‘Of course. What can I tell you?’ McIver nodded.

‘Frobisher,’ Pitt replied. ‘Expatriate Englishman living here in St Malo. Would he be the right man to approach to ask a small service to his country? Please be candid. It is of . . . importance, your understand?’

‘Oh quite – quite.’ McIver leaned forward a little. ‘I beg you, sir, consider very carefully. I don’t know your business, of course, but Frobisher is not a serious man.’ He made a slight gesture of distaste. ‘He likes to cultivate some very odd friends. He pretends to be a socialist, you know, a man of the people. But between you and me, it is entirely a pose. He mistakes untidiness and a certain levity of manner for being an ordinary man of limited means.’ He shook his head. ‘He potters around and considers it to be working with his hands, as if he had the discipline of an artisan who must work to live, but he has very substantial means, which he has no intention of sharing with others, believe me.’

Although Pitt had begun to wonder if there were anything more to Frobisher than the comfortable way of life there seemed, he still felt a sinking of bitter disappointment from McIver’s words. If this were not what West had been going to tell them about, and for which he had been killed, then why was Wrexham still here? Why had men like Linsky and Meister visited?

‘Are you sure?’ he said as politely as he could. However he said it, he was still questioning McIver’s judgement.

‘As sure as anyone can be,’ McIver replied. ‘Made a lot of noise, prancing about striking poses, but never done a thing in his life.’

‘He had some very violent and well-known people visiting him.’ Pitt clung to the argument, unwilling to concede that they had spent over a week here for nothing, still more, that West had died for a farce, a piece of pointless pretence.

‘See ’em yourself?’ McIver asked.

‘Yes. One of them in particular is very distinctive,’ Pitt told him. Then even as he said it, he realised how easy it was to ape a man as unusual as Linsky. He had never seen Linsky except in photographs, taken at a distance. The hatchet features, the greasy hair would not be so hard to copy. And Jacob Meister was ordinary enough.

But why? What was the purpose of it all?

That too was now hideously clear – to distract Pitt and Gower from their real purpose. It had succeeded brilliantly, until this moment. Even now, Pitt was confused, struggling to make sense, and with no idea what to do next.

‘I’m sorry,’ McIver said sadly. ‘But the man’s an ass. I can’t say differently. You’d be a fool to trust him in anything that matters. And I hardly imagine you’d have come this far for something trivial. I’m not as young as I used to be, and I don’t get into St Malo very often, but if there’s anything I can do, you have only to name it, you know.’

Pitt forced himself to smile. ‘Thank you, but it would really need a resident of St Malo. But I’m grateful to you for saving me from making a bad mistake.’

‘Think nothing of it.’ McIver brushed it away with a gesture. ‘I say, do have some more cheese. Nobody makes a cheese like the French – except perhaps the Wensleydale, or a good Caerphilly.’

Pitt smiled. ‘I like a double Gloucester, myself.’

‘Yes, yes,’ McIver agreed. ‘I forgot that. Well, we’ll grant the cheese equal status. But you can’t beat a good French wine!’

‘You can’t even equal it,’ Pitt agreed.

McIver poured them both some wine, then leaned back in his chair. ‘Do tell me, sir, what is the latest news on the cricket? Here I hardly ever get the scores, and even then they’re late. How are Somerset doing?’

In the east the darkness was no more than a fading in the sky, a purpling of the colour behind the streamers of cloud.

He went over what they knew in his mind again, carefully, all he had seen or heard himself, and all that Gower had seen and reported.

It did not make sense, therefore there must be something missing. Or something seen but misunderstood?

A carter passed him on the road, the wheels sending up clouds of dust, and he smelled the pleasant odour of horses’ sweat and fresh-turned earth. The man grunted at Pitt in French, and Pitt returned the greeting as well as he could.

The sun was sinking rapidly now, the sky filling with hot colour. The soft breeze whispered in the grass and the new leaves on the willows, always the first to open. A flock of birds rose from the small copse of trees a hundred yards away, swirled up into the sky and circled round.

Between them Pitt and Gower had seen just enough to believe it was worth watching Frobisher’s house. If they arrested Wrexham now, it would unquestionably show everyone that Special Branch was aware of their plans, so they would automatically change them.

They should have arrested Wrexham in London. He would have told them nothing, but they had learned nothing anyway. All they had really done was waste time.

How had he allowed that to happen? West had arranged the meeting, promising extraordinary information. Pitt could see the letter in his mind, the scrawled, misspelled words, the jagged edges of fear in the letters, the smudged ink.

No one but Pitt himself and Gower knew of it. How had Wrexham learned? Who had betrayed West? It had to be one of the men plotting whatever it was that poor West had been going to reveal.

But they had not followed West. Pitt and Gower were on his heels from the minute he began to run. If there had been anyone else running they would have to have seen him. Whoever it was must have been waiting for West. How had they known he would run that way? It was pure chance. He could as easily have gone in any other direction. Pitt and Gower had cornered him there, Pitt along the main street, Gower circling around to cut him off.

Had West run into Wrexham by the most hideous mischance?

Pitt retraced in his mind the exact route they had taken. He knew the streets well enough to picture every step, and see the map of it in his mind. He knew where they had first seen West, where he had started to run and which way he had gone. There had been no one else in the crowd running. West had darted across the street and disappeared for an instant. Gower had gone after him, jabbing his arm to indicate which way Pitt should go, the shorter way, so they could cut him off.

Then West had seen Gower and swerved. Pitt had lost them both for a few minutes, but he knew the streets well enough to know which way West would go, and been there within seconds . . . and Gower had raced up from the right to come up beside Pitt.

But the right dog-legged back to the street where Pitt had run the minute before, not the way Gower had gone. Unless he had passed Wrexham? Wrexham had come from the opposite way, not following West at all. So why had West run so frantically, as if he knew death was on his heels?

Pitt stumbled in the road and came to a stop. Because it was not Wrexham West was afraid of, it was either Pitt himself, or Gower. He had no reason to fear Pitt. Gower was a superb runner. He could have been there before, ducked back into the shelter of the alley entrance and then burst out of it again as Pitt arrived. It was he who had killed West, not Wrexham. West’s blood was already pooled on the stones. Pitt could see it in his mind’s eye. Wrexham was the harmless man he appeared to be, the decoy to lure Pitt to St Malo, and keep him here, while whatever was really happening came to its climax somewhere else.

It had to be London, otherwise it was pointless to lure Pitt away from it.

Gower. In fifteen or twenty minutes Pitt would be inside the walls of St Malo again, back to their lodgings. Almost certainly Gower would be there waiting for him. Suddenly he was no longer the pleasant, ambitious young man he had seemed only this morning. Now he was a clever and extremely dangerous stranger, a man Pitt knew only in the most superficial way. He knew that Gower slept well, that his skin burned in the sun, that he liked chocolate cake, that he was occasionally careless when he shaved himself. He was attracted to women with dark hair and he could sing rather well. Pitt had no idea where he came from, what he believed, or even where his loyalties were – all the things that mattered, that would govern what he would do when the mask was off.

Now suddenly Pitt must wear a mask as well. His own life might depend on it. He remembered with a chill how efficiently West had been killed, his throat cut in one movement, and his body left on the stones, bleeding to death. One error and Pitt could end the same way. Who in St Malo would think it more than a horrific street crime? No doubt Gower would be first on the scene again, full of horror and dismay.

There was no one Pitt could turn to. No one in France even knew who he was, and London could be in another world for all the help it could offer now. Even if he sent a telegram to Narraway it would make no difference. Gower would simply disappear, anywhere in Europe.

He started to walk again. The sun was on the horizon and within minutes it would be gone. It would be almost dark by the time he was within the vast city walls. He had perhaps fifteen minutes to make up his mind. He must be totally prepared once he reached the house. One mistake, one slip, and it would be his last.

He thought of the chase to the East End, and finally the railway station. He realised with acute self-blame how easily Gower had led him, always making sure they did not lose Wrexham completely, and yet the chase seemed natural enough to be real. They lost him momentarily, and it was always Gower who found him. It was Gower who stopped Pitt from arresting him, pointing out the use of watching him and learning more. Gower had had enough money in his pocket to buy tickets on the ferry.

Come to that, it was Gower who said he had seen Linsky and Meister, and Pitt had believed him.

What was Wrexham? Part of the plan to take Pitt away from London, knowing precisely what he was doing, and why? Then why had he not actually killed West? Too squeamish? Too afraid? Not paid enough?

Of course Pitt must go back to London; the question was what to say to Gower. What reason should he give? He would know there was no message from Lisson Grove. Had there been, it would have been delivered to the house, and simple enough to check on anyway. All Gower would have to do was ask at the post office.

The sun was already half gone, a burning orange semicircle above the purple horizon. Shadows were deepening right across the road.

Should Pitt try to elude him, simply go straight to the harbour now, and wait for the next boat to Southampton? But that might not be till tomorrow morning; and Gower would realise what had happened, and come after him some time during the night. Pitt didn’t even have the rest of his clothes with him. He was wearing only a light jacket in the warm afternoon.

The idea of fighting Gower here was not to be considered. Even if he could subdue him – and that was doubtful; Gower was younger and extremely fit – what would Pitt do with him? He had no power to arrest him. Could he leave him tied up, and then escape – assuming he were successful anyway?

But Gower would not be alone here. That thought sobered him like a drench of cold water, raising goose bumps on his skin. How many of the people at Frobisher’s house were part of his plan? The only answer was for Pitt to deceive him, make him believe that he had no suspicions at all, and that would not be easy. The slightest change in manner and he would know. Even a selfconsciousness, a hesitation, a phrase too carefully chosen, and he would be aware.

How could Pitt tell him they were returning to London? What excuse would he believe?

Or should he suggest he himself return, and Gower stay here and watch Frobisher and Wrexham, just in case there were something after all? In case Meister or Linsky came back? Or anyone else they would recognise? The thought was an immense relief. A weight lifted off him as if it were a breathtaking escape, a flight into freedom. He would be alone – safe. Gower would stay here in France.

A second later he despised himself for his cowardice. When he had first gone on the beat in London, as a young man, he had expected a certain amount of violence. Indeed, now and then he had met with it. There had been a number of wild chases, with a degree of brawling at the end. But after promotion, as a detective he had almost exclusively used his mind. There had been long days, even longer nights. The emotional horror had been intense, the pressure to solve a case before a killer struck again, before the public were outraged and the police force disgraced. And after arrest there was testimony at the trial. Worst of all was the fear, which often kept him awake at night, that he had not caught the right man, or woman. Perhaps he had made a mistake, believed a lie, drawn a wrong conclusion, missed something, and it was an innocent person who was going to face the hangman.

But it was not physical violence. The battle of wits had not threatened his own life. He was chilled in the first darkness of the early evening. The sunset breeze was cold on his skin, and yet he was sweating. He must control himself. Gower would see nervousness; he would be watching for it. The suspicion that he had been found out would be the first thing to leap to his mind, not the last.

Before he reached the house, Pitt must have thought of what he would say, and then he must do it perfectly.

‘Can I get you a glass of wine?’ he offered. ‘I expect you’re hungry?’

For a moment Pitt was attacked by doubt. Was he being ridiculous thinking that this man had swiftly and brutally killed West, and then turned with an innocent face and helped Pitt pursue Wrexham all the way to Southampton, and across the Channel to France?

He mustn’t hesitate. Gower was expecting an answer, an easy and natural response to a very simple question.

‘Yes I am,’ he said with slight grimace as he sank into the other chair and realised how exhausted he was. ‘Haven’t walked that far in a while.’

‘Nine or ten miles?’ Gower raised his eyebrows. He set the wine down on the table near Pitt’s hand. ‘Did you have any luncheon?’ He resumed his own seat, looking at Pitt curiously.

‘Bread and cheese, and a good wine,’ Pitt answered. ‘I’m not sure red is the thing with cheese, but it was very agreeable. It wasn’t Stilton,’ he added, in case Gower should think him ignorant of gentlemen’s habit of taking port with Stilton. They were sitting with wine, like friends, and talking about etiquette, as if no one were dead, and they were on the same side. He must be careful never to allow the absurdity of it to blind him to its lethal reality.

‘Worth the walk?’ Gower enquired. There was no edge to his voice; his lean brown hand holding the glass was perfectly steady.

‘Yes,’ Pitt said. ‘Yes it was. He confirmed what I suspected. It seems Frobisher is a poseur. He has talked about radical social reform for years, but still lives in more or less luxury himself. He gives to the occasional charity, but then so do most people of means. Talking about action seems to be his way of shocking people, gaining a degree of attention for himself while remaining perfectly comfortable.’

‘And Wrexham?’ Gower asked.

There was a moment’s silence in the room. Somewhere outside a dog was barking, and much further away someone sang a bawdy song and there was a bellow of laughter. Pitt knew it was vulgar because the intonation of the words was the same in any language.

‘Obviously a different matter,’ Pitt replied. ‘We know that for ourselves, unfortunately. What he is doing here I have no idea. I hadn’t thought he knew we were after him, but perhaps I was wrong in that.’ He let the suggestion hang in the air.

‘We were careful,’ Gower said, as if turning the idea over in his mind. ‘But why stay here with Frobisher if all he is doing is trying to escape from us? Why not go on to Paris, or anywhere?’ He put down his glass and faced Pitt. ‘At best he’s a revolutionary, at worst an anarchist wanting to destroy all order and replace it with chaos.’ There was stinging contempt in his voice. If it was false then he belonged on the stage.

Pitt rethought his plan. ‘Perhaps he’s waiting here for someone, and he feels safe enough not to care about us?’ he suggested.

‘Or whoever’s coming is so important he has to take the risk?’ Gower countered.

‘Exactly.’ Pitt settled himself more comfortably in his chair. ‘But we could wait a long time for that, or possibly fail to recognise it when it happens. I think we need a great deal more information.’

‘French police?’ Gower said doubtfully. He moved his position also, but to one less comfortable, as if any moment he might stand up again.

Pitt forced himself not to copy him. He must appear totally relaxed.

‘Their interests might not be the same as ours,’ Gower went on. ‘Do you trust them, sir? In fact, do you really want to tell them what we know about Wrexham, and why we’re here?’ His expression was anxious, bordering on critical, as if it were only his junior rank that held him back from stronger comment.

Pitt made himself smile. ‘No, I don’t,’ he answered. ‘To all your questions. We have no idea what they know, and no way of checking anything they may tell us. And, of course, our interests may very well not be the same. But most of all, as you say, I don’t want them to know who we are.’

Gower blinked. ‘So what are you suggesting, sir?’

Now was the only chance Pitt was going to have. He wanted to stand up, to have the advantage of balance, even of weight, if Gower moved suddenly. He had to stiffen his muscles and then deliberately relax to prevent himself from doing it. Carefully he slid a little further down in the seat, stretching his legs as if they were tired – which was not difficult after his ten-mile walk. Thank heaven he had good boots, although they looked dusty and scuffed now.

‘I’ll go back to London and see what they have at Lisson Grove,’ he answered. ‘They may have much more detailed information they haven’t given us. You stay here and watch Frobisher and Wrexham. I know that will be more difficult on your own, but I haven’t seen them do anything after dark other than entertain a little.’ He wanted to add more, to explain, but it would cause suspicion. He was Gower’s superior. He did not have to justify himself. To do so would be to break the pattern, and if Gower were clever, that in itself would alarm him.

‘Yes, sir, if you think that’s best. When will you be back? Shall I keep the room on here for you?’ Gower asked.

‘Yes – please. I don’t suppose I’ll be more than a couple of days, maybe three. I feel we’re working in the dark at the moment.’

‘Right, sir. Fancy a spot of dinner now? I found a new café today. Has the best mussel soup you’ve ever tasted.’

‘Good idea.’ Pitt rose to his feet a little stiffly. ‘I’ll leave first ferry in the morning.’

Or had Gower suspected something already? Did he know, even as Pitt walked down to the harbour along ancient, now-familiar streets, that the pretence was over? He had a desperate instinct to swing round and see if anyone were following him. Would he pick out Gower’s fair head, taller than the average, and know it was he? Or might he already have changed his appearance and could be yards away, and Pitt had no idea?

But his allies, Frobisher’s men, or Wrexham’s, could be anyone: the old man in the fisherman’s jersey, lounging in a doorway, taking his first cigarette of the day; the man on the bicycle bumping over the cobbles; even the young woman with the laundry. Why suppose that Gower himself would follow him? Why suppose that he had noticed anything different at all? The new realisation loomed gigantic to him, filling his mind, driving out almost everything else. But how self-centred to suppose that Gower had nothing more urgent to consume his thoughts! Perhaps Pitt and what he knew, or believed he knew, was an irrelevance anyway.

He increased his pace and passed a group of travellers heaving along shopping bags and tightly packed portmanteaux. On the dockside he glanced around as if to search for someone he knew, and was flooded with relief when he saw only strangers.

He stood in the queue to buy his ticket, and then again to get on board. Once he felt the slight sway of the deck under his feet, the faint movement, even here in the harbour, it was as if he had reached some haven of safety. The gulls wheeled and circled overhead, crying harshly. Here on the water the wind was sharper, salt-smelling.

Pitt stood on the deck by the railing, staring at the gangway and the dockside. To anyone else, he hoped he looked like someone looking back at the town with pleasure, perhaps at a holiday well spent, possibly even at friends he might not see again for another year. Actually he was watching the figures on the quay, searching for anyone familiar, any of the men he had seen arriving or leaving Frobisher’s house, or for Gower himself.

Twice he thought he saw him, and it turned out to be a stranger. It was simply the fair hair, an angle of shoulder or head. He was angry with himself for the fear that he knew was largely in his mind. Perhaps it was so deep because, until the walk back to the town yesterday evening, it had never entered his mind that Gower had killed West, and Wrexham was either a co-conspirator, or even just a tissue-paper socialist posing as a fanatic, like Frobisher himself. It was the shock at his own blindness that dismayed Pitt. How stupid he had been, how insensitive to possibilities. He would be ashamed to tell Narraway, but he would have to; there would be no escaping it.

At last they cast off and moved out into the bay. Pitt remained where he was at the rail, watching the towers and walls of the city recede. The sunlight was bright on the water, glittering sharp. They passed the rocky outcrops, tide slapping around the feet of the minor fortress built there, guarding the approaches. There were few sailing boats this early: just fishermen pulling up the lobster pots that had been out all night.

Pitt tried to imprint the scene on his mind. He would tell Charlotte about it: the beauty, the tastes and sounds, how it was like stepping back in time. He should bring her here one day, take her to dine where the shellfish was so superb. She hardly ever left London, let alone England. It would be fun, different. He imagined seeing her again so vividly he could almost smell the perfume of her hair, hear her voice in his mind. He would tell her about the city, the sea, the tastes and the sounds of it all. He wouldn’t have to dwell on the events that had brought him to France, only on the good.

Someone bumped against him and, for a moment he forgot to be startled. Then the chill ran through him, and he realised how his attention had wandered.

The man apologised.

Pitt spoke with difficulty, his mouth dry. ‘It’s nothing.’

The man smiled. ‘Lost my balance. Not used to the sea.’

Pitt nodded, but he moved away from the rail and went back into the main cabin. He stayed there for the rest of the crossing, drinking tea and having a breakfast of fresh bread, cheese and a little sliced ham. He tried to look as if he were at ease.

When they reached Southampton he went ashore carrying the light case he had bought in France and looking like any other holidaymaker returning home. It was midday. The quayside was busy with people disembarking, or waiting to take the next ferry out.

He went straight to the railway station, eager to catch the first available train to London. He would go home, wash and dress in clean clothes. Then, if he were lucky, just have time to catch Narraway before he left Lisson Grove for the evening. Thank heavens for the telephone. At least he would be able to call and arrange to meet with him wherever was convenient. Maybe with his news about Gower, a rendezvous at Narraway’s home would be better.

He felt easier now. France seemed very far away, and he had had no glimpse of Gower on the boat. He must have satisfied him with his explanation.

The station was unusually busy, crowded with people all seemingly in an ill humour. He discovered why when he bought his ticket for London.

‘Sorry, sir,’ the ticket seller said wearily. ‘We got a problem at Shoreham-by-Sea, so there’s a delay.’

‘How long a delay?’

‘Can’t say, sir. Maybe an hour or more.’

‘But the train is running?’ Pitt insisted. Suddenly he was anxious to leave Southampton, as if it were still dangerous.

‘Yes, sir, it will be. D’yer want a ticket fer it or not?’

‘Yes, I do. There’s no other way to London, is there?’

‘No, sir, not unless yer want ter take a different route. Some folk are doing that, but it’s longer, an’ more expensive. Trouble’ll be cleared soon, I dare say.’

‘Thank you. I’ll have one ticket to London, please.’

‘Return, sir? Would you like first, second or third class?’

‘Just one way, thank you, and second class will be fine.’

He paid for it and went back towards the platform, which was getting steadily more and more crowded. He couldn’t even pace backward and forward to release some of the tension that was mounting inside him, as it seemed to be for everyone else. Women were trying to comfort fretful children; businessmen pulled pocket watches out of their waistcoats and stared at the time again and again. Pitt kept glancing around him, but there was no sign of Gower, although he was not sure if he would have noticed him in the ever-increasing crowd.

He bought a sandwich and a pint of cider at two o’clock, when there was still no news. At three he eventually took the train to Worthing, and hoped to catch another train from there, perhaps to London via a different route. At least leaving Southampton gave him an illusion of achieving something. As he made his way towards a seat in the last carriage, again he had the feeling of having escaped.

The carriage was nearly full. He was fortunate there was room for him to sit. Everyone else had been waiting for some time and they were all tired, anxious and looking forward to getting home. Even if this train did not take them all the way, at least they were moving. One woman held a crying two-year-old, trying to comfort her. The little girl was rubbing her eyes and sniffing. It made Pitt think of Jemima at that age. How long ago that seemed. Pitt guessed she had been on holiday and was now confused as to where she was going next, and why. He had some sympathy for her, and it made him engage the mother in conversation for the first two stops. Then the movement of the train and the rhythmic clatter over the connections on the rail lulled the child to sleep, and the mother finally relaxed.

Several people got off at Bognor Regis, and more at Angmering. By the time they reached Worthing and stopped altogether, there were only half a dozen people left in Pitt’s carriage.

‘Sorry, gents,’ the guard said, tipping his cap back a little and scratching his head. ‘This is as far as we go till they get the track cleared at Shoreham.’

There was a lot of grumbling, but the few passengers remaining got out of the carriage. They walked up and down the platform restlessly, bothered the porters and the guard asking questions to which no one had answers, or went into the waiting room with passengers from the other carriages.

Pitt picked up someone else’s discarded newspaper and glanced through it. Nothing in particular caught his eye, and he kept looking up every time someone passed, in the hope that there was news of the train leaving again.

Once or twice, as the long afternoon wore on, he got up and walked the length of the platform. With difficulty he resisted the temptation to pester the guard, but he knew that the poor man was probably as frustrated as everyone else, and would have been only too delighted to have news to give people.

Finally, as the sun was on the horizon, they boarded a new train and slowly pulled out of the station. The relief was absurdly out of proportion. They had been in no hardship and no danger, yet people were smiling, talking to each other, even laughing.

The next stop was Shoreham-by-Sea, where the trouble had been, then Hove. By then it was dusk, the light golden and casting heavy shadows. For Pitt this hour of the evening had a peculiar beauty, almost with a touch of sadness that sharpened its emotional power. He felt it even more in the autumn, when the harvest fields in the country were stubbled gold, the stooks like some remnant of an earlier forgotten age, more barbaric, without the inroads of civilisation on the land. He thought of his childhood at the big house where his parents had worked, of the woods and fields, and a sense of belonging.

Suddenly the carriage enclosed him. He stood up and went to the end and through the door onto the small platform before the next carriage. It was mostly for men to light cigars without the smoke being unpleasant to other passengers, but it was a good place to stand and feel the rush of air, and smell the ploughed earth and the damp of the woods as they passed. Not many trains had these spaces. He had heard somewhere that it was an American invention. He liked it very much.

The air was quite cold, but there was a sweetness to it and he was happy to remain there, even though it grew darker quickly, heavy clouds rolling in from the north. Probably some time in the night it would rain.

He considered what he would tell Narraway of what now seemed to be an abortive trip to France, and how he would explain his conclusions about Gower and his own blindness in not having understood the truth from the beginning. Then he thought with intense pleasure of seeing Charlotte, and of being at home where he had only to look up and she would be there, smiling at him. If she thought he had been stupid, she would not say so – at least not at first. She would let him say it, and then ruefully agree. That would take away most of the sting.

It was nearly dark now; the clouds had brought the night unnaturally soon.

Without any warning he was aware of someone behind him. With the rattle of the wheels he had not heard the carriage door open. He half turned, but was too late. The weight was there in the middle of his back, his right arm was locked in a fierce grip, his left pinned against the rail by his own body.

He tried to step backwards onto the instep of the man, shock him with the pain of it. He felt the man wince, but there was no easing of the hold of him. He was being pushed forward, twisted a little. His arm was crushed on the rail and he gasped to get his breath. He was pushed so his head was far out over the speeding ground. The wind was cold on his face, smuts from the engine striking him, stinging. Any minute he was going to lose his balance and then it would be a second, two, and he would be over the edge and down onto the sleepers. At this speed he would be killed. The fall would probably snap his spine. The man was strong and heavy. The weight of him was driving the breath out of Pitt’s chest, and he had no leverage to fight back. It would be over in seconds.

Then there was a slam of carriage doors, and a wild shout. The pressure on Pitt’s back was worse, driving the last bit of air out of his lungs. He heard a cry, and realised it was from himself. The weight lifted suddenly and he gasped, hanging onto the rail, scrambling to turn round, coughing violently. The man who had attacked him was struggling with someone else, who was portly, thick-waisted. He could see only shadows and outlines in the dark. The man’s hat flew off and was carried away. He was already getting the worst of the fight, backing towards the rail at the other side. In the momentary light from the door his face was contorted with anger and the beginning of terror as he knew he was losing.

Pitt straightened up and threw himself at the attacker. He had no weapon except his fists. He struck the man low in the chest, as hard as he could, hoping to wind him. He heard him grunt and he pitched forward, but only a step. The fat man slithered sideways and down onto one knee. At least that way he would not overbalance across the rail and onto the track.

Pitt followed his attacker, striking again, but the man must have expected it. He went down also and Pitt’s blow only caught the edge of his shoulder. The man twisted with it, but for no more than a moment. Then he lunged back at Pitt, his head down, catching Pitt in the stomach and sending him sprawling. The carriage door was slamming open and closed.

The fat man scrambled to his feet and charged, his face red, shouting something indistinguishable over the howl of the wind and roar and clatter of the train. He dived at Pitt’s attacker, who stepped out of the way, and then swivelled round and raised himself. He grasped the fat man and heaved him over the rail to fall, screaming, arms flailing helplessly, out onto the track.

For a second Pitt was frozen with horror. Then he turned and stared at the man who had attacked him. He was only an outline in the dark, but he did not need to hear him speak to recognise him.

‘How did you know?’ Gower asked, curiosity keen, his voice almost normal.

Pitt was struggling to get his breath. His lungs hurt, his ribs ached where the rail had bruised him, but all he could think of was the man who had tried to rescue him, and whose broken body was now lying on the track.

Gower took a step towards him. ‘The man you walked ten miles to see, did he tell you something?’

‘Only that Frobisher was a paper tiger,’ Pitt replied, his mind racing now. ‘Wrexham can’t have taken so long to work that out, so maybe he always knew it. Then I thought perhaps he was just the same. I thought I saw him cut West’s throat, but when I went over it step by step, I didn’t. It just looked like it. Actually West’s blood was already pooled on the stones. You were the one who had the chase, all the way to the ferry. I thought you were clever, but then I realised how easy it had been. It was always you who found him when we lost him, or who stopped us actually catching him. The whole pursuit was performed for my benefit, to get me away from London.’

Gower gave a short burst of laughter. ‘The great Pitt, whom Narraway sets so much store by. Took you over a week to work that out! You’re getting slow. Or perhaps you always were. Just lucky.’

Then suddenly he flung himself forward, arms outstretched to grasp Pitt by the throat, but Pitt was ready this time. He ducked and charged, low, with his head down. He caught Gower in the belly just above the waist, and heard him gasp. He straightened his legs, lifting Gower off the ground. His own impetus carried him on, high over the rail and into the darkness. Pitt did not even see him land, but he knew with a violent sorrow that it had to have killed him instantly. No one could survive such an impact.

He straightened up slowly, his legs weak, his body shaking. He had to cling onto the rail to support himself.

The carriage door slammed shut again, then opened. The guard stood there, wide-eyed, terrified, the lantern in his hand, the carriage lights yellow behind him.

‘Ye’re a lunatic!’ he cried, stuttering over his words.

‘He was trying to kill me!’ Pitt protested, taking a step forward.

The guard jerked the lantern up as if it were some kind of shield. ‘Don’t you touch me!’ His voice was shrill with terror. ‘I got ’alf a dozen good men ’ere ’oo’ll tie yer down, so I ’ave. Ye’re a bleedin’ madman. Yer killed poor Mr Summers as well, ’oo only came out there ter’elp the other gent.’

‘I didn’t . . .’ Pitt began, but he didn’t get to finish the sentence. Two burly men were crowding behind the guard, one of them with a walking stick, the other with a sharp-ended umbrella, both held up as weapons.

‘We’re gonna put yer in my van,’ the guard went on. ‘An’ if we ’ave ter knock yer senseless ter do it. Just gimme the excuse, is all I ask. I liked Mr Summers. ’E were a good man, an’ all.’

Pitt had no wish to be beaten into submission. Dazed, aching and appalled at what he had done, he went without resisting.