A perfect summer night ends in a deadly crash - and four lives are changed forever. On a warm evening the students of Nantucket High gather for the traditional graduation bonfire on the beach. But the celebration ends in tragedy after a horrible car crash leaves the driver, Penny Alistair, dead, and her twin brother Hobby, in a coma. Penny’s boyfriend, Jake and her friend Demeter, are unhurt but haunted by the events of that night, and the questions that linger about what happened in the car - and what happened in the dunes before Penny took the wheel.