Three men emerge from the wooden building: two in dishdashes, and a smaller man dressed neatly in hiking boots, jeans and a blue button-down shirt. The hollering teenagers fall silent and back away from the helicopter as these men approach. The smaller man wears glasses. His face is lined, his hair is beginning to go gray, but he is still trim and fit. Except for the little fur pouch hanging on a gold chain around his neck, he looks like a middle manager on casual day, would fit neatly into any Western street scene.

Veronica sees Derek start suddenly, as if remembering something. He says something that sounds like "euthanasia."

One of the two men in dishdashes is black, short but hugely muscled, like a professional wrestler. The other is lighter-skinned, Middle Eastern. He shouts to the men in the back of the helicopter in a guttural language that must be Arabic. Veronica moans when she hears this. It feels like final confirmation that Derek's worst-case scenario is somehow, unbelievably, exactly what has happened. They have been seized by Islamic terrorists.

Derek turns to Veronica and demands in a shaking, angry voice, "Was it you?"

She stares at him. He has gone pale, every muscle in his face is taut, he is trembling. She isn't even sure she heard him correctly in the wake of the deafening helicopter noise.

He says, louder, though she can still hardly hear him, "You fucking answer me. Did you set me up? Was it you?"

"I don't know what you're talking about," Veronica manages, totally baffled.

"Don't you lie to me."

"I'm not lying. I don't -"

"Did your husband send you?" he demands.

"What are you talking about? I'm not even married."

"You were. To Danton DeWitt. Did he send you?"

Veronica gapes at him. The world seems to spin around her. She has never spoken Danton's name to Derek or any of her other fellow captives. "How - how do you even know who he is?"

"Did you know he was involved? Is that why you came to Africa?"

"Involved in what?" she bleats.

Derek looks at her, then back to man in glasses outside the helicopter, who has withdrawn something metal and plastic, something familiar, from his shoulder bag. The device is so out of place it takes Veronica a second to identify it as a small handheld videocamera. He puts it to his eye and records as the black men in dishdashes grab the white captives and half-lead, half-drag them away from the aircraft. The Arabic man stays where he is, holding a curved and gleaming panga. Veronica thinks of the American hostages taken in Iraq, captured by insurgents and beheaded alive. She feels dizzy again.

The air smells of wet decay. The ground of the airstrip is not so much grass as dense weeds cut to ankle height, furrowed in places by muddy tire marks. Dozens of gunmen surround them in a circle several rows thick, like an audience for a particularly good street performer. The Arabic man steps up to the roped-together line of captives. Veronica, who is at the front of the line, freezes as he lifts his panga. He cuts her free. Then he cuts loose Derek behind her, grabs him by the back of his neck, shoves him roughly to a point about ten feet away from the others, and gives his panga to another man in a dishdash, the one who looks like a bodybuilder.

"This is a setup," Derek shouts to Jacob, the words spilling out of him, talking as fast as he can. "This was never a random kidnapping, this is a fucking execution. Islamists and interahamwe, working together, that's exactly what I was here to investigate, someone set me up -"

The Arabic man punches him in the stomach. Derek falls to his knees on the airstrip, doubled over, the wind knocked out of him, gasping for air. Then the massive bodybuilder man lifts his panga high and brings it down in a glittering arc so fast Veronica doesn't even have time to scream. Blood spurts from the back of Derek's neck and he collapses onto his belly. His attacker drops to one knee and his panga rises and falls again, and then a third time. Veronica can't scream, none of them can, it is too awful, she can barely breathe. Derek's head rolls forward from his body, leaving a ragged, bloodsoaked discontinuity at his neck. Blood gouts onto the weeds. Veronica's mind reels, but she can't look away. It feels almost like there is something wrong with her vision, not with Derek, like if she looks hard enough she will see his head above his shoulders, rather than the pale knob of his severed spine set in crimson flesh and torn flaps of skin.

Somebody grabs the back of Veronica's neck, pulls her around, leads her past the helicopter, across the airstrip, towards the edge of the gorge. She is vaguely aware that the faint animal keening she hears is coming from her own throat. The others are dragged behind her. The middle-aged man with the camera finishes his close-ups of Derek's beheaded corpse and comes up beside her, walking sideways, filming their staggering march like some kind of demented tourist. The Arabic man walks on their other side, in view of the camera. Veronica wonders if they are going to be thrown off the edge of the gorge. It seems very likely, but she doesn't struggle. She feels like she has been strapped into a runaway train, has lost even theoretical control over anything that happens to her. Derek is dead. They actually cut his head off. Veronica knows intellectually she should try to fight, to run, but the idea seems ridiculous, she is helpless, escape is hopeless. It is easier to just detach herself from what is happening, to watch as if from a great distance, as if she is just a temporary passenger in this body.

There is a trailhead at the edge of the cliff, a narrow and treacherous path that zigzags and switchbacks down the steep and rocky slope to the muddy gorge below. Veronica is thrust onto the trail so hard that without her arms to right herself she very nearly overbalances and falls to her death. Instead she falls and scrapes her right leg bloody. She gets up and immediately begins to descend the trail, she needs no encouragement, all she wants is to get away from the horror she just witnessed.

The valley floor below has been reduced to a swamp of red mud gouged into hills, mounds, fissures and craters. At least a hundred men are labouring here, digging from the riverbed, dumping muck into what looks like giant wooden bathtubs, pouring water into those tubs with buckets, sifting through what remains. Others hold whips and pangas and move among the workers, watching hawklike. Veronica sees a small group of armed men at each end of the gorge, where violent rapids begin. The base of the other side has been so hollowed out that the massive cliff above now forms a slight overhang. A ragged wooden shelter has been built in its shadow.

Veronica's feet squelch into wet mud. She has finally reached the bottom of the gorge. She looks up and back. The other captives are a minute behind her, still roped together, forced to move at the pace of their slowest member, probably Diane. The three men in dishdashes follow them, as does the small man in glasses. The videocamera swings on a strap from his shoulder as he navigates the steep trail.

The gorge is maybe a hundred feet across. Work near her has slowed or stopped as both labourers and overseers turn to watch their pale-skinned visitors. Veronica takes two deep breaths. Then she starts to run. She doesn't think she has much of a chance, but she has to try, they're going to kill her.

The mud sucks at her feet, it's more a stumbling jog than a run. She angles towards the river, avoiding the nearby workers. Nobody seems to react for what feels like a long time; people stare but do nothing, as if she is a crazy person on the street, best avoided. Then she finally hears shouts from up above, and some of the overseers, the men carrying whips, move to intercept her. But they are too late, she has reached the main flow of the river. She dives into it with all the strength that remains in her legs. It is shallower than she hoped, only waist-deep, with a bottom of mixed mud and gravel, but it flows fast enough to carry her past the first two overseers before they reach her.

She tries to kick and paddle, to accelerate downstream. It's hard to keep her head above water with her arms tied behind her back. Nobody seems to have jumped after her. She distantly remembers reading somewhere that most Africans can't swim. Then she remembers why, it's because their lakes and rivers are infested with crocodiles, but never mind that, she'll worry about four-legged predators once she gets away from these two-legged ones. She twists her body and lifts her head and catches a glimpse of the four gunmen at the end of the gorge, stationed just before the river plunges over a rocky cliff. The spray from the rapids beyond rises above their heads. She remembers seeing the valley from above, how it was bracketed on both sides by fierce whitewater. If the rapids don't get her then the crocodiles and the Congo jungle probably will, but at least this way she has a chance, however small. She knows she won't be followed, it's like Butch Cassidy and the Sundance Kid, no one who didn't absolutely have to would go into these rapids.

The roar of the water quickly becomes thunderous, the river sweeps her downstream faster than she expected, the current is accelerating. She has to writhe for every breath, she can't hold a steady position. One of the gunmen steps into the river and reaches out to catch her. Veronica curls into a ball. He grabs at her - and her foot pistons out into his crotch. He lets her go immediately and sits down comically, clutching himself, and then her stomach lurches as the river sweeps her over a six-foot drop and into a deep, violent cataract of churning whitewater.

Veronica is flung in one direction, then pulled in another, scraped painfully along a painful wall of rock, forced suddenly downwards, and pinned on her back against the river bottom by a relentless jackhammering flow of water that feels like a wall. She can't break free, the water is far too strong, she isn't even sure which way is up. All she knows is that she is trapped and she is running out of breath.

Don't panic, she tells herself. If you panic you're dead. Her arms are behind her. That's something. She grabs at the darkness and her fingers close on sharp rock. She tries to pull herself sideways, crabwise, instead of fighting the full brunt of the current. She isn't strong enough, not even close, she exerts all her remaining strength and succeeds in shifting herself only an inch - but this is enough to break the equilibrium. Suddenly she is torn from the watery prison and catapulted back up to the surface, just long enough to grab a breath before she is dragged back into the river. Its power is overwhelming, she is like a feather in heavy surf, the notion of fighting for any kind of control is laughable. She will go where the water takes her. Veronica curls into a ball and hopes for the best. Seconds later her head slams into solid rock and everything goes dark.