Excerpt from I See You by Clare Mackintosh, plus links to reviews, author biography & more

"I guess so." As the train slowed down for Oxford Circus, the woman began moving toward the doors. "I hope it's a quiet one for you."

That's jinxed it, Kelly thought. She glanced at her watch. Nine stops to Stratford: ditch her stuff, then head back. Home by eight, maybe eight thirty. In again for seven a.m. She yawned hard, not bothering to cover her mouth, and wondered if there was any food at home. She shared a house near Elephant and Castle with three others, whose full names she knew only from the rent checks pinned neatly to the board in the hall, ready for collection each month. The sitting room had been converted to a bedroom by a landlord keen to maximize his income, leaving the small kitchen the one communal area. There was only room for two chairs, but her housemates' shift patterns and erratic hours meant Kelly could go days without seeing anyone at all. The woman in the biggest bedroom, Dawn, was a nurse. Younger than Kelly, but far more domesticated, Dawn occasionally left a portion for Kelly on the side by the microwave, with one of her bright pink Post-it notes telling Kelly to help yourself! Her stomach rumbled at the thought of food, and she glanced at her watch. The afternoon had been busier than she'd thought; she was going to have to put in some extra hours next week, or she'd never get through it all.

A handful of businessmen got on at Holborn and Kelly cast a practiced eye over them. At first glance they looked identical, with their short hair, dark suits, and briefcases. The devil was in the detail, Kelly thought. She searched out the faint pinstripe; the title of a book pushed carelessly into a bag; wire-framed glasses with a kink in one arm; a brown leather watch strap beneath a white cotton shirtsleeve. The idiosyncrasies and appearance tics that made them stand out in a lineup of near-identical men. Kelly watched them openly, dispassionately. She was just practicing, she told herself, not caring when one of them looked up and found her cool gaze on him. She thought he might look away, but instead he winked, his mouth moving into a confident smile. Kelly's eyes flicked to his left hand. Married. White, well-built, around six foot tall, with a shadow around his jaw that probably wasn't there a few hours ago. The yellow flash of a forgotten dry-cleaning tag on the inside of his overcoat. Standing so straight she'd put money on ex-military. Nondescript in appearance, but Kelly would know him if they met again.

Satisfied, she turned her attention to the latest influx of passengers, getting on at Bank and filtering through the carriage to find the remaining few seats. Almost everyone had a phone in their hand: playing games, listening to music, or simply clutching it as though grafted to their palm. At the other end of the carriage someone lifted their phone in front of them and Kelly instinctively turned away. Tourists, getting an iconic shot of the London Underground to show back home, but she found the idea of being background scenery in someone's holiday snaps too weird to contemplate.

Her shoulder ached where she'd slammed into a wall, taking the corner too tight as she ran down the escalators and onto the platform at Marble Arch. She'd been seconds too late, and it annoyed her that the blooming bruise on her upper arm was in vain. She'd be quicker next time.

The train pulled into Liverpool Street; a throng of people waiting on the platform, impatient for the doors to open.

Kelly's pulse quickened.

There, in the center of the crowd, half-hidden beneath oversized jeans, a hooded top, and a baseball cap, was Carl. Instantly recognizable and—desperate though Kelly was to get home—impossible to walk away from. It was clear from the way he melted into the crowd that Carl had seen Kelly a split second before she had seen him, and was equally unenthusiastic about the encounter. She was going to have to move fast.

Excerpted from I See You by Clare Mackintosh. Copyright © 2017 by Clare Mackintosh. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.