Christine Lucas once woke every morning with no memory of the day before.

Her name, her past, her family – all of it vanished overnight. Every morning, she had to piece together her life again, never knowing what to trust, never realising the danger was far closer than she could ever imagine.

She survived. Just.

Now, years later, Christine is living under an assumed name, in an isolated cottage where no one can find her. She tells herself she is safe. She tells herself the worst is behind her.

Then strange things start happening. Her phone is not where she left it. There is a book by her bed she does not remember buying. A stranger appears on the lane. And when Christine runs a bath, the scent of the water carries her back to something she has spent years trying to forget.

She is terrified that her amnesia is returning.

But if it isn't, who wants her to believe it is?

Christine Lucas returns, in the long-awaited new novel from the author of the multi-million-copy bestseller Before I Go to Sleep, named one of The New York Times' 50 Best Thrillers of the 21st Century.