A message is received by the U.S.S. Appleby from American soldiers in the Caroline Islands who say they can no longer hold off the Japanese. Since the war ended 17 years prior, Lt. Rex St. John (Jack Mullaney) thinks it's a gag from Ensign O'Toole (Dean Jones). Lt. Commander Stoner (Jack Albertson) orders a search of the island. After some comedic misunderstandings, the men finally convince the American holdouts that they are also American and that the war is over. The search party is told that there are Japanese on the island who also don't realize the war is over. As the men make their way back to the Appleby, O'Toole and Seaman Gabby Di Julio (Harvey Lembeck, "The Phil Silvers Show") goes in search of the Japanese. Lt. St. John and the rest of his party comes across the Japanese soldiers instead and are held prisoner. O'Toole, Di Julio, Commander Stoner, and Chief Petty Officer Homer Nelson (Jay C. Flippen) regroup to go after their men. They too are captured and O'Toole tries to reason with the Japanese Sgt. Harada (Mako) and Pvt. Osano (James Hong, who is still going strong in films here in March 2017). When they convince the Japanese soldiers they're more trouble than they're worth the outcome is not what they anticipated.
