Two Los Angeles homicide detectives are sent to a remote Alaskan town, where the sun never sets in summer, to investigate the brutal murder of a teenage girl. The veteran Will Dormer, also hounded by an internal investigation into his methods, makes a fatal mistake during an operation in the fog that begins to gnaw at his conscience. Deprived of sleep by the perpetual light and pressured by a suspect who knows too much, his sanity erodes night after sleepless night. A psychological thriller from Christopher Nolan, somber and morally ambiguous, with Al Pacino and Robin Williams pitted against each other in a duel of guilt and manipulation.