When Susie decides to invite her old school friends for a reunion she tells herself that it's just about showing off. It's about letting Amanda, Izzy and Tamsin, see how well she's done, with her successful career as an artist, her gorgeous house in France, her deliciously louche boyfriend. But the truth is that this is a dark plan. A plan that could make or break her seemingly perfect life...and she knows it. As the old friends gather at Susie's for a long weekend of catching up and comparisons, it is clear that despite their lives having taken very different turns, they are all still haunted by a dark and common past. They each know that up until now they have been treading water -- waiting for the inevitable moment when they have to face the truth. The question is, now that the time has come, who will sink and who will swim?