For six long years, Hamilton High School seniors Kelly, Jude, Wendy and Nick have been hiding the truth of what happened to 10-year-old Robin Hammond the day her broken body was discovered near an old abandoned convent. They kept secret how they taunted Robin - backed her into a corner until, frightened, she stood on a window ledge and fell to her death. Fearing they'd be held responsible, they vowed never to tell. However, someone else was there that day and now, is ready to exact their revenge - on prom night.