Director: George B. Seitz
This is the VHS release (see more).
SummaryTwo tugboat captains join the Navy in World War I. They put aside their longstanding rivalry and unite to battle the U-boats. In one scene, one of the captains, who has been taken prisoner aboard a U-boat, alerts his comrade in a nearby ship by tapping Morse code on the inside of the U-boat's hull.
NotesMade with the assistance of the US Navy, this film's release date was advanced at the request of the US Government due to the gathering war clouds. Offering a clearly pro-interventionist message, the movie begins with a narration describing the U-boat "raiders" which attacked the US coast in 1918.