The Ward (2010)

A thriller centered on an institutionalized young woman who becomes terrorized by a ghost. In 1966, Kristen (Amber Heard), an amnesiac arsonist, is committed to a psychiatric unit where therapist Dr. Stringer (Jared Harris) is treating a gaggle of disturbed girls who seem to be haunted by the angry spirit of a mysteriously departed patient. Unable to convince the staff that the patients are in danger, Kristen makes persistent escape attempts.