At Doddsville County High, awkward science whiz Marty Rantzen hides out in the chemistry lab, the only place safe from the whispers and cruelty that follow him through the halls. When the school's reigning drama queen, Carol, lures him into the girls' locker room, Marty believes, briefly, that he's finally been seen. Instead, it's a brutal April Fool's Day prank, staged to strip him of his dignity and leave him shattered. Broken and humiliated, Marty retreats to the lab, where a drug-laced joint and careless tampering trigger a horrific accident that leaves him permanently scarred. Five years later, eight former classmates receive an invitation to a reunion on April 1st. Drawn back to their abandoned high school, they break in to escape a storm and begin to celebrate ... until the doors lock behind them. What unfolds is no reunion at all. Someone from their past has returned with only one thing on their mind: vengeance.