Several platforms had merged into an apron where departing passengers pushed past him to get to their trains as the arrivals queued up to go through the turnstiles. Eli, lost in thought as he waited his turn to shuffle forward and place his identity pass on the scanner, started at a harsh buzzing from one of the turnstiles. A petite, remarkably pretty woman stood on his side of the barrier, the rejected pass in her hand, as she stared at the flashing light on the machine.

She looked vaguely familiar, but unlike the sense of almost-recognition he’d had with Zavcka Klist, Eli knew that what he was identifying here was a type, not an individual. It was something about her littleness and delicacy of bone structure, her excessive prettiness and the shyness with which she carried it. She stood out in a way that had become rare since the Syndrome. Even Klist did not exceed the usual height-weight-attractiveness ratios nearly as much as this woman. Yet there was something incoherent about her, some subtle counteraction to her beauty. He was no follower of fashion, but he sensed that something about her appearance was wrong.

He was struck by her hair. It was shoulder length and stylishly cut, but the dull, matt-black colour was at odds with her modish grooming and fashionable clothes. Eli felt a glimmer of satisfaction at identifying the disguise. He considered whether it was a wig or a dye job, decided on dye. A wig might slip, and besides if this woman had decided to take such a risk she’d have chosen a better wig. No, she’d dyed her hair, poured on layers and layers of light-barring pigments and fixatives to block the telltale gem glow. He wondered what colour it really was. A gentle rose pink maybe, or pale lilac.

For the briefest moment she raised her eyes to the man who was waiting for her on the other side of the barrier. He looked at least twenty years older, and better at hiding his discomfiture. His hair was receding and grey, and he wore the kind of well-cut, conservative suit that made Eli think of a banker. He had a confident, well-cared-for air. Someone used to money and privilege, universal rights and automatic respect. Definitely not a gem.

‘Must be due for renewal,’ the man said, in a voice intended to carry. Although he was looking at the black-haired woman, Eli thought the comment was meant for the turnstile guards. The one on the bodyscanner was watching the woman keenly. Those adjacent to her in the crowd took in her looks and her unease, and edged away. The woman bit her lip as she carefully lowered the pass onto the scanner again. This time a soft, welcoming tone accompanied a steady green light as the barrier gates hissed open. The woman stepped through and prodded her slim climbcase into the luggage scanner.

Intrigued, Eli sidestepped into the queue for the same turnstile to watch what happened. He was certain the woman was a gem, travelling on a forged – or stolen – norm pass. It was a serious violation, and on the face of it an irrational one. Gem travel had not been restricted since the Declaration – not yet anyway – and she would have been allowed through on her own pass.

But then she would have been recorded as having arrived in London. He could think of two reasons she might wish to avoid that. One was common to any criminal, gem or norm, who wanted to cover their tracks as they moved from city to city. The other was specific to gems who simply wanted to disappear, fall off the index of the underclass and slip into norm society. If their appearance allowed them to pass, the cleanest break with their old life was to register in a new location under their new identity.

He thought the latter was more likely in this case. There was something about the woman that seemed inconsistent with a city-hopping professional crook. Her nervousness and her companion both suggested someone unused to this kind of endeavour. He wondered if the man was a lover, a well-heeled gent past his prime but with the means and nous to attract a beautiful companion who would be grateful for the life he could offer. Such cases were not unknown; were not even restricted to the rich. It was very much at odds, he thought, with Zavcka Klist’s analysis.

The climbcase hissed swiftly through the automatic sensors, and paused rather longer at the visualisation monitor. Eli could see a guard bending down to peer at the screen. He knew this was a waste of time: the chemical sensors and hazard-recognition software were much more perceptive than human faculties. The same was true of the bodyscanners. The guards were really there to deal with the people and luggage that the machines flagged up, not to identify problems themselves. Until a year ago they had had very limited authority to intervene once the equipment had signalled acceptance, but this had been extended as part of the hodgepodge of post-Declaration protocols. Approval by the scanners of papers, person and possessions no longer guaranteed swift passage.

Which was why Eli wanted to see what would happen if – as he suspected – the woman did not set off the bodyscanner. She stepped up to and through it with a bit more confidence, and stood on the exit mat waiting for the light to turn green. No physical abnormalities then, no strange internal anatomy. The guard glanced at the monitor, then peered around it to give her a long look. Eli thought he was manually overriding the lights to keep her on the mat. He was focused on her hair. She stood perfectly still, barely breathing, still biting her lip, not lifting her eyes from the ground.

A mistake, that, thought Eli. It would be more natural to glance over at him, see what’s taking so long. He found he was holding his breath too, waiting for the guard to press a button that would make the lights flash red, to stand up and ask the woman to step aside and follow me, please. She seemed resigned to it. He could see her companion draw himself up in readiness.