Aviel was hopelessly lost and there was only one way to get back on track, though she was reluctant to try the scent potion again just yet. Her stomach muscles still ached, and when she stretched she felt a sharp pain to the left of her belly button, as if she had torn something there.

Her map said that it was forty miles from Casyme to Gothryme, a couple of days’ ride at her slow pace, but even in daylight she struggled to reconcile the lines on the paper with the landscape she was passing through.

There were no towns or villages here, no farmers to ask for directions, and somehow she had taken a wrong turning. It was late afternoon and the track was taking her up a ridge through tall, dripping forest.

How could this be right? The track did not appear to have been used in weeks. She stopped at a little cascade, where Thistle drank noisily, deposited an enormous amount of manure on the bank and cropped the grass. She urged him up to the top of the ridge and dismounted, wincing.

Her bottom was bruised all over and the insides of her thighs were chafed again. She looked left and right and up, though she could only see ridges, rising ever higher, and hints of snow on the tops of the highest.

Aviel consulted her map again but it was hard to focus on the lines; having had so little sleep last night, she was exhausted. Was there any point going on? She made mistakes when she was tired and her bad luck was always worse. It was after four in the afternoon now, and the sun had passed behind the mountains ages ago. Better find a safe campsite and get a fire going. She still felt shivery whenever she thought about what had happened in the night, and that stinking brute coming after her.

Through the trees she glimpsed the ruins of a mill, its rotting waterwheel still in place. It would be good to have walls around her again, even broken ones. She limped across to Thistle, took hold of the saddle and tried to lift her good foot into the stirrup. Pain speared through her ankle and her thigh muscles gave way; she could not raise her foot high enough. She tried again but was too low by a foot.

Tears of frustration sprang into her eyes. She wiped them on her sleeve, cursing her turned ankle and the miserable luck that had plagued her all her life.

“We’ll just have to walk, Thistle. That’ll be nice, won’t it?”

Thistle turned his long head, looked her in the eye and snorted.

Aviel looped the reins around her fist. They crossed a cascade. The light was fading; it was getting cold and a ground mist was rising. She glanced to her left and saw the wheel again and the broken black walls behind it. And she recognised it – she had seen it after sniffing the graveolence. Had it led her here? If so, why?

“Home, sweet home, Thistle!”

Thistle whinnied; his eye was huge and the white was showing all around.

“It’s all right,” she said, stroking his neck. “We’re safe here.”

The ground mist rose in a series of wraith shapes. A chilly breeze twisted and coiled, then drifted the shapes towards her. She passed through one and it chilled her to her aching bones.

The mill loomed up. It had been built over the stream on the wall that dammed it, and the dam still stood. The stone walls were covered in moss as high as her head, and the mill was dank and unwelcoming, but it was the best shelter she was going to get. Aviel tied Thistle on a long lead so he could crop the grass and reach the water, and went in through a broken archway.

The mill had once been two storeys, but its roof had fallen in and the wood of the upper floor had rotted away except for a couple of beams festooned with wraith-like fungal growths. The ground was littered with decayed timbers and broken roof slates. Parts of the far wall had collapsed, leaving a series of ragged stone stumps like scattered teeth in a black jawbone.

Home sweet home indeed! She found some dry boards in the lee of the left-hand wall and used a little bag of tinder she had brought with her to light a fire.

It sputtered and shot sparks at her, and the smoke hung low between the walls. It had an unpleasant smell; the boards had been painted with wood tar to preserve them, and Aviel started to feel nauseous. She sniffed some oil of orange blossom, which helped, then took a blazing board outside to look for more dry wood. She found none; everything was sodden, and now it began to rain.

Thoroughly dispirited, she ate a lump of hard cheese, found a dry corner, put out the reeking fire and lay down in her sleeping pouch with her cloak wrapped around her. But though she was utterly exhausted, Aviel could not get to sleep.

With her hammer and her pint of oil, smashing the summon stone and burning the fragments should be easy enough. But she had to think of all the ways it could go wrong. The stone might be in a place that was dangerous to get to, or it might be protected in some way.

She was too tired. She closed her eyes and tried to put everything out of mind, and finally slipped into a troubled sleep.

The purple-faced man made his drunken way east across the mountains. He rode the last of his horses to death, abandoned it in the middle of the road and continued in a grunting lurch, swilling from a flask until it was empty then smashing it to pieces on the road, wrenching another from his saddlebags and continuing. Once, when his agony broke through the numbing effects of the drink, he screamed until blood ran from his nose.

He met an old man driving a cart and singing an offensively merry tune. He leaped onto the cart and threw the old man off on his head, cursing him for being happy in so wretched a world. The drunk turned the cart around and ran over the old man, then flogged the old horse into a gallop until it collapsed. He ate nothing and did not stop, day or night.

The rampage went on, one mindless brutality after another until the drunk crested the range of mountains separating the dry lands to the west from wealthy Iagador. There he stopped, took a fragment of dusty glass out of his pocket and sniffed it. He pointed a brass tube with two red crystals on its end to the left, then the right, his eyes blazing, then settled on a direction and staggered on. He had to stop her before she ruined everything.

Aviel screamed and threw herself out of the sleeping pouch. The stench had congealed in her nostrils, a reek so offensive that it made the Eureka Graveolence seem like a cleansing aroma.

“It’s him!” she gasped. “It’s him.”