Below on AllMovie

Reflecting studio executives' taste for material that crosses genres, this film from director David Twohy and co-screenwriter Darren Aronofsky mixes the war movie and supernatural thriller genres. After they rescue a trio of survivors that includes a nurse, Claire Page (Olivia Williams), from a British hospital ship sunk by the Nazis, the crew of the American submarine U.S.S. Tiger Shark comes to believe that their vessel is haunted. The unexpected death of their commander forces first officer Lt. Brice (Bruce Greenwood) to take command, trying to avoid a German destroyer on the hunt for his ship, while investigating the series of mysterious incidents that are terrifying his crew. Is the Tiger Shark haunted, or is there something otherworldly inhabiting the waters where the sailors are currently trapped? Originally entitled "Proteus," this project was slated to be Aronofsky's follow-up to Pi (1998), but the writer/director opted to helm Requiem for a Dream (2000) instead. Below co-stars Scott Foley, Zach Galifianakis, Dexter Fletcher, and Holt McCallany.