Sally is watching the news with her husband when she hears a name she ought not to recognise: Mark Bretherick.

Last year, a business trip Sally had planned was cancelled at the last minute. Desperate for a break from her busy life juggling her career and a young family, Sally didn't tell her husband that the trip had fallen through. Instead, she booked a week off and treated herself to a secret holiday. All she wanted was a bit of peace - some time to herself - but it didn't work out that way. Because Sally met a man - Mark Bretherick.

All the details are the same: where he lives, his job, his wife Geraldine and daughter Lucy. Except that the man on the news is a man Sally has never seen before. And Geraldine and Lucy Bretherick are both dead . . .