In the autumn of 1944, the submarine USS Aspro slipped out of Fremantle and into the vast expanse of the South China Sea. This was her fifth war patrol, a mission that would test the nerves of her crew and the steel of the boat against Japan’s desperate efforts to keep its sea lanes open.

For weeks the men endured the grind of patrol life, stalking convoys, dodging aircraft, and bracing against the thundering shocks of depth charges. The climax came on October 2, 1944, when Aspro closed in on a Japanese tanker hugging the coastline. With torpedoes running true and enemy aircraft swooping low, the crew fought their way through one of the most dangerous encounters of their patrol.

Tonight we tell the story of Aspro’s fifth war patrol, the men who carried it out, and the day when courage and precision made all the difference.