Three strangers are trapped inside an elevator in an empty apartment building during a blackout. The asthmatic Claudia is traumatized with the accident with her beloved grandmother due to a moment of distraction. Karl is a widow doctor that loves his daughter. Tommy is a young man that has just accidentally killed the violent father of his girlfriend Francesca while protecting her and is planning to runaway to Paris with her. The tension of group escalates to a nightmare when one of the strangers shows that is a psychopath and sadistic serial-killer.