Minesweeper.

Lt. Richard Houston is an officer in the U.S. Navy who deserted during peacetime service to escape gambling debts, and took up life as a hobo. The Japanese attack on Pearl Harbor spurs him to rejoin the Navy under the assumed name of Jim "Tennessee" Smith. Houston is assigned to serve aboard a minesweeper, where he carries out numerous successful efforts to defuse mines in the San Diego harbor. Houston gets involved in a love triangle, competing with Seaman Elliot Nash for the affections of Mary Smith (Jean Parker)