It's Violet's twelfth birthday party, and her classmates decide to play a cruel prank with rabbit masks and knives... that ends with death. The mystery goes unsolved for eighteen years, until Violet Woods returns to her old hometown of Twilight Falls nearing her thirtieth birthday, and ends up meeting all her old schoolmates again. She decides to solve the mystery of which one was the killer at her birthday party back then, which brings the killer back to their old tricks...
The story is told from Violet's perspective, but wanders back to eighteen years ago each chapter to the view of one of her classmates, showing that each kid from back then had dark secrets, and maybe even reasons for what happened.