A German sub destroys a rowboat, a buoy, and another German sub (obviously, not the pride of the fleet). Meanwhile, Popeye, with a boat full of "spinach fer Britain", rams into the sub by accident. The sub cuts Popeye's ship in half with machine-gun fire, separating him from the spinach; it then sends a torpedo into the remains, which Popeye collects in a rowboat. Popeye spins the sub upside down, then ends up in a mine field (again barely saving the spinach). After another run-in, the spinach lands in the sub, and Popeye ends up underwater, where he opens his own can and smashes the Nazis into the mine field. He rows the sub full of spinach into the fog, and ultimately right to #10 Downing Street.

Bluto the blacksmith gets a draft notice. Popeye is in charge of the local draft board. Bluto gives a sob story about his ailments, but makes a miraculous recovery when Popeye's gorgeous "secretary" appears (really a 1000 pound weight in disguise). Bluto, desperate, dives out the skyscraper window; Popeye tries to catch him, but they both plummet through the sidewalk, and the devil chases them back out of hell. Bluto dashes into traffic, but the car suffers more. He then drops a safe on his head, but ends up inside, along with Popeye. Bluto tosses the safe (with Popeye) into an orphanage, where Japanese are plotting in secret. Bluto shows up in time to help, but they're quickly overpowered, so Popeye shares his spinach with Bluto and they team up; their American fist is then felt overseas by both Hirohito and Hitler. Bluto signs up, but he needs help spelling his name.