Russian submarine X3 is seen in action, torpedoing an enemy ship.
Titles read: "SOVIET SUBMARINE IN ACTION".
Various shots of the Russian submarine X3. It is seen on the surface of the sea, then submerging on a search for the enemy. The crew go about their duties and the Captain keeps an eye on the periscope. Torpedoes are fired.
L/S through the periscope of a burning ship which the submarine's torpedoes have struck.