The USS Sea Cat (SS-399) was a Balao-class submarine built by the Portsmouth Navy Yard and commissioned on 16 May 1944. Following a shakedown cruise, the Sea Cat traveled to the Souther China Sea to begin operation in a wolf pack with the submarines USS Pampanito (SS-383), Pipefish (SS-388), and Sea Raven (SS-196).
While her commanding officer was convinced that her torpedoes found their mark against two merchant ships, postwar Japanese records dispute the claim. By winter, a tired Sea Cat crew sailed into Guam having spent 61 days at sea.
In February of 1945, the Sea Cat set out in the East China Sea as part of a wolf pack. The submarines operated off the coast of Japan, using gunfire to attack and damage a 300-ton cargo vessel. The Sea Cat also reported sinking a 2,000-ton cargo ship with torpedoes. Postwar records, however, do not back up this claim. The patrol came to a close of 24 March 1945 and she was not to set out again until 27 April 1945.