Marie Langham is devastated when her childhood friend, Nina, is diagnosed with a terminal illness. Before Nina passes away, she asks Marie to look out for her family--her son, daughter, and husband, Stuart. Marie would do anything for Nina, so of course she agrees.   Following Nina s death, Marie gradually finds herself drawn into her friend s life--her family, her large house in the countryside. But when Camilla, a mutual friend from their old art-college days, suddenly reappears, Marie begins to suspect that she has a hidden agenda. And this hunch proves correct when Marie discovers that Nina had long-buried secrets--secrets about a holiday in Ibiza the women took ten years previously, when Marie s then-boyfriend went missing after a tragic accident and was later found dead.   Marie used to envy Nina s beautiful life, but now she feels increasingly trapped in its ever-shrinking world. As she becomes more and more isolated, M