Single mother Sally Lachlan has a secret that has haunted her for a decade, although perhaps it is time to let it go. A chance meeting with a fellow scientist, the charismatic geneticist Anthony Blake, reawakens her desire for love. But as Sally finally lets down her guard, her teenage daughter Charlie begins to ask questions about her late father. As Sally delves into her history, guided by her therapist Helen, old events are turned over and examined - memories of her husband Jeff, her friend Zoë, and what really happened between the three of them all those years ago. Both the past and the future are places Sally prefers not to think about, but if she wants to find happiness, she must first come to terms with her previous marriage. Only then can she be honest with Charlie?and herself.