The depth of their courage knew no bounds.

Academy Award nominee James Caan commands a covert naval operation in this riveting drama inspired by an amazing true story discovered in declassified British War Office files. With "first-class underwater photography" (Variety) and taut suspense, Submarine X-1 is an action-packed epic of heroism and sacrifice.

Commander Bolton (Caan) has lost his submarine, the Gauntlet, in a sea battle with the Nazis in 1943. Although the survivors still blame him, he's cleared of charges and assigned to lead a top-secret training program with three experimental miniature X-1 subs, each manned by a crew of only four. Their mission: to sink the mighty battleship Lindendorf - the same ship that destroyed the Gauntlet!