The Sunday Times bestseller and Richard & Judy Book Club author of Sleep returns with her most gripping book yet.

Ursula, Gareth and Alice have never met before. Ursula thinks she killed the love of her life. Gareth's been receiving strange postcards. And Alice is being stalked. None of them are used to relying on others - but when the three strangers' lives unexpectedly collide, there's only one thing for it: they have to stick together. Otherwise, one of them will die.

Three strangers, two secrets, one terrifying evening.

The million-copy bestseller returns with a gripping new novel that will keep you guessing until the end.