When USS Aspro (SS-309) pushed away from USS Euryale at Fremantle on September 10, 1944, she was no stranger to the deadly chess game of the Pacific submarine campaign. She had already carried out four successful patrols, sending enemy ships to the bottom, and she bore the scars and the confidence of a seasoned hunter. Her crew, lean from the tropical heat and the endless diet of Navy rations, carried the rhythm of submarine life in their bones. They had endured the long refit—tuning machinery, testing torpedoes, restowing provisions, and saying goodbye to the brief comforts of liberty. Now they were heading back into the South China Sea, where enemy shipping still plied the waters in defiance of the American blockade.