Tris stopped, took a slow look around her and did what she did best.

Reconstructed events from the facts stacking up inside her mind. It wasn't intelligence that let her do this, though Tris sometimes told herself that it was. And even Doc Joyce seemed to buy into the idea of her intelligence. At least he pretended he did.

No, it was coldness. This stacking up of facts, sifting of ideas and synthesis of both into a conclusion was about protection and distance. About protecting herself from the world outside her and keeping her distance from those not drawn like moths to the same cold flame.

"I've been tried," said a voice in her head. "I'm not interested in overturning the conviction."

Tris blinked.

The man beside the huge expanse of water was standing up, waiting calmly as other men moved towards him, shackling his hands behind his back while a woman looked on.

"I'll call Gene," said the woman. "See what he says."

Tris looked from the rope that held the sleeping bag secure to the overhang, then looked at the tether still knotted around her thighs, the one which ran from between her legs, under her padded jacket and up to a steel spike in the rock-face. And finally she looked at the rope she'd been avoiding.

It was cut very cleanly, probably by the bare blade now resting in the bottom of the sleeping bag. And there was something else: the bag remained sealed along the side Luca had chosen. Which meant... Tris tried to clarify in her head exactly what this meant and rather began to wish she hadn't.

Cold and alone, Luca had unzipped the molecules along his edge of the sleeping bag, climbed out to hang in space and then leant across to seal the bag again before cutting himself free and falling to his death.

He'd sealed the bag to keep Tris safe, to prevent her absent-mindedly kicking the knife or spikes out of the bag or rolling out herself into the night wind to panic as she twisted on her short length of tether.

Tris could think of half a dozen practical, utterly prosaic reasons why Luca might have done what he did. But she couldn't think of the reason, not the one that really made sense.

"Shit," she said to herself. It was hard to remain furious with someone who'd sacrificed himself to let you live.

"If that's what he did," said the voice in her head.

"What else?"

"Despair."

"At what?" The girl's voice was contemptuous.

"The sheer scale of that descent."

Tris shook her head, even as she picked up his satchel and put it over her shoulder. The knife went through her belt, its cold edge rather too close to Tris's hips for her liking. And then she clambered out of the sleeping bag, yanked down her trousers and pissed into the cold air.

"It's time to start," said the voice.

"Yes," Tris said. "I've already worked that out." She took a final look at the silver haze above her where other worlds formed their fractured shell around the distant sun.

She would have to leave the sleeping bag where it was, because only Luca knew how to turn it from cloak into a bivouac or bag and back again and it was much too cumbersome to carry.

"Move," Tris said.

"Yeah," she said. "I know."

"Well, do it."

Tris was talking to herself again.

CHAPTER 53

Marrakech, Summer 1977 [Then]

Prisoner Zero knew when things went wrong exactly. A few minutes after the early evening call to prayer had finished echoing from the minaret of La Koutoubia, when Idries hurried into Chez Luz, a two-room café off Djemaa el Fna used by the men in Moz's part of the Mellah, and sat himself opposite Moz and Malika without being invited.

"Malika was still alive at this point?"

Prisoner Zero nodded. "This was before."

"And Malika didn't like Idries?"

"Nobody liked Idries," Prisoner Zero said. He was telling Petra Mayer why he decided to carry drugs for Hassan after all.

"What do you want?" Moz made no attempt to hide his irritation. The rat-faced boy was Hassan's bagman, little more. These days he might dress like Hassan in a suit cut to the European style, but the garment looked as stupid on Idries as it looked stylish on bagman.

"We've been waiting for you."

"We?"

"Hassan," said Idries quickly. "Hassan's been waiting."

"Then let him wait," Malika said. She was the only girl in a café full of old men wearing jellabas, a couple of middle-aged men in suits and the two teenaged boys. Only Moz was close enough to see that her hands were trembling.

"It pays," said Idries, smiling at the look on the other boy's face. It was a particularly rat-faced smile, even for Idries. "Hassan said that would interest you."

"How much?" said Moz.

"Depends," Idries said.

"On what?" Most conversations with Idries were like this. Unsatisfactory exchanges of minimal amounts of information. Idries spoke out of the corner of his mouth and chain-smoked Gitanes. The result of too many afternoons watching black and white Belmondo films at a cinema behind Boulevard Safi.

"Whether it's two of you or one." Idries glanced at Malika. "It's in a smart area of the Nouvelle Ville," he added. "So she can't dress like that."

"What's wrong with my clothes?" Malika demanded.

Idries ignored her.

"How much?" demanded Moz, bringing the discussion back to the thing that mattered. "And what's the job?"

"Hassan will tell you," Idries said. "Meet him in an hour outside the café opposite the market on Mohammed the Fifth." As an afterthought, Idries turned back to address Malika. "Any chance you own a hijab?"

The answer was no, but Malika could borrow one. Come to that, she could steal one freshly washed off the wall behind her house and claim a sudden, God-inspired attack of modesty if she got caught. The old crows were quite stupid enough to believe that.

"Find one," Idries said, "and wear something that covers your arms." He stood without offering to pay for the pastries he'd taken from the plate in the centre of their table and threaded his way towards the door, sneering at the old jellaba-clad men.

Idries made a real point of not looking back.

"Here," Moz said, pausing to tear a piece of cake in two and offer half to Malika, "you need to eat."

Malika shook her head, her red hair hidden and her face framed by the black folds of a haik. She looked beautiful. A beauty that only highlighted the set of her mouth and the anger in her cat-like eyes as she stalked across Place de Foucauld into Avenue Mohammed V, catching her reflection in the first shop window.

"Look at me."

"You look great," Moz insisted. Only this time flattery was not enough. And so Malika strode ahead and the boy in the black jeans and weird T-shirt hurried to keep up.

"It pays," Moz said.

Malika snorted. "One of these days," she said, "Hassan's going to get you into real trouble."

The avenue around them was beginning to fill as those in the Old City came out for the evening. A few tourists hurried passed the edge of Parc Lyautey, heads down, wearing shirts that were too thick, the wrong cut or just too tight for the heat, but mostly this stretch of Mohammed V was filled with Marrakchi in traditional dress.

Ahead of Malika and Moz bicycles, mopeds and donkey carts streamed through Bab Larissa, scenting the air with burning oil and the sweet smell of animal sweat and dung.

"Look," Moz said. "I need to make my peace with Hassan."

And Malika finally halted, ignoring the scowls of the old men around her as she touched her fingers to a bruise on Moz's cheek.

"What about this?"

Moz shrugged. "I've been thinking," he said, "Hassan's going to be somebody. You and me..." He looked into the eyes of the girl opposite. "We're just going to be ourselves. And maybe that's enough."