The second U.S. submarine to bear the name “Argonaut,” the SS-475, was laid down on 28 June 1944 by the Portsmouth, New Hampshire, Navy Yard. She was launched on 1 October 1944 and placed in commission, under the command of Lieutenant Commander John Sneed Schmidt on 15 January 1945.
Following her shakedown cruise, the Argonaut sailed for Key West, Florida, to conduct tests on lighter-than-air craft and to train with the Fleet Sound School. Soon after these operations, the Argonaut transited to Hawaii and arrived in Pearl Harbor on 11 June 1945. After a series of exercises and several repairs, she departed Pearl Harbor for her first war patrol on 28 June 1945, during which she was to travel to the East China and Yellow Seas to search for Japanese shipping. On 16 July, the Argonaut rescued a downed aviator and transferred him to the U.S. submarine Quillback (SS-424). On 12 August, the Argonaut sank a 25-ton cargo junk with fire from her 40-mm and 20-mm guns. Soon afterward Japan surrendered, and that was to be the Argonaut's only combat action during her brief episode of wartime service.