Teenagers, Tilly, Monica, Peter and Allison are involved in a car crash. Allison dies from her injuries and at her memorial Allison's uncle confronts the group and blames them for her death. Monica suggests that they get out of town and stay at her grandparents' summerhouse in the countryside to work through the grief of losing their friend and to be out of sight until things have calmed down. When they get to the summerhouse everything is normal and peaceful until a masked man starts to terrorize and punish them in the most horrific ways.