Biba and her handsome brother Rex live in a beautiful, rambling house in north London; naive Karen is soon lured into their dissolute circle, spending an idyllic summer whiling away the hours in a haze of booze and sex. The story runs along two strands – we flash backwards to the start of the trio’s relationship from the present day, when Rex emerges from prison to return home with Karen and their daughter. Someone is watching this family in their clapboard home by the sea as they try to build a new life. But why? The answer lies in the past.