Kate Forman has an enviable life: a loving family and a perfect husband, Paul. But one night she finds Paul drunk and covered in blood, mumbling about having killed something - or someone.

When a young and attractive woman who works for Paul is found murdered, Kate's suspicions about what he has really done send her on an increasingly desperate search for the truth that threatens to smash her carefully constructed life.

Doing the right thing should seem obvious, but as the lies multiply, the truth is not as straightforward as it seems; how well do you know the person you're married to?