Chrysanthemum Willet, known as Chrys, arrives at a new school after a turbulent personal history and is assigned to Mason Raymore's former locker. Mason Raymore, a celebrated athlete, is already a lingering presence in the school's collective memory, shaping how students like Dean Jackson interpret anything tied to him. Chrys's cousin Rel Taylor stays close as she tries to settle in, while Dean Jackson, Grace Browning, Ellie Gains, and teacher Mr Craven orbit a growing unease tied to an unfamiliar object found within the locker. As the group becomes increasingly entangled, small disturbances begin to affect their routines, relationships, and sense of safety, pushing them toward an uneasy awareness that something beyond explanation has entered their lives.