Two married couples: Kate and Cary, Cressida and Luke. Four people who meet, click, and become firm friends. But then Kate and Luke discover a growing attraction, which becomes an obsession. They fall in love, then fall into an affair. It blows their worlds apart. After the fall, nothing will ever be the same again. A gripping insight into the anatomy of an affair in the tradition of Anita Shreve, Josephine Hart and Anne Tyler.