A warm June evening, a local tradition: the students of Nantucket High have gathered for a bonfire on the beach. What begins as a graduation night celebration ends in tragedy after a horrible car crash leaves the driver, Penny Alistair, dead, and her twin brother in a coma. The other passengers, Penny's boyfriend, Jake, and her friend Demeter, are physically unhurt--but the emotional damage is overwhelming. Questions linger about what happened before Penny took the wheel.

As summer unfolds, startling truths are revealed about the survivors and their parents, the secrets kept, promises broken, and hearts betrayed.