Miles to go before I sleep

Christine wakes up, confused and frightened. She does not know where she is; the man in bed with her is a stranger. Patiently and kindly, he explains: he is her husband, Ben, and he loves her. She suffers from a brain injury that prevents her from remembering more than one day's events. Whenever she goes to sleep, she forgets everything. Ben shows her pictures of their life together.

How long ago? she asks. When she was twenty-seven, he tells her. They've been having this conversation every morning for twenty years.

That's the setup of Before I Go To Sleep by S. J. Watson. At first it seems like a heartwarming tale of a loving marriage that's endured in spite Christine's disabling short-term memory problem. Then things get sinister: Christine finds a journal, written by herself, headed with these words: "DON'T TRUST BEN."

Christine depends upon Ben utterly for everything she knows about herself and her life. But for some reason, at some point, she began to doubt him - and to write the journal, cataloging what she knows, and what Ben isn't telling her.

Watson's narrative cleverly tantalizes the reader - With no memories to base her conclusions on, how can Christine know anything for sure? Is Ben a villain? Is Christine just a raging paranoiac? And how can she find out the truth before she forgets everything again?

The narrative technique isn't flawless. Christine must have lots of time alone every day to secretly read her journal, and then to write down each day's discoveries. As the journal gets longer and longer, the setup gets a little improbable - sometimes the husband seems to go away specifically so that she can update the journal.

Still, it's an exciting and suspenseful book, full of poignant moments and shocking surprises, and it's satisfying the way the puzzles introduced in the first confusing pages are solved one by one. If you like psychological thrillers, give Before I Go To Sleep a try.