The Stooges want to fly for the Royal Air Force, but end up as mechanics working in a motor-pool garage. When given the assignment of getting a 'squeak' out of the General's car from the his assistant Kelly (Duke York), they get sidetracked after Moe's head gets stuck in a pipe. After several painful attempts, they finally unscrew Moe from the tight quarters, and he eventually chases Larry and Curly around the vehicle, breaking the windshield in the process. The Stooges disassemble the entire engine, and are still puzzled, as they are not exactly certain what a squeak looks like. Kelly comes to retrieve the General's car, with the Stooges still hoping to be airmen.
The trio promptly evacuate the garage after Kelly realizes what they have done, only to end up hiding out in a bomb mistaken for a sewer pipe. The bomb is then dropped behind enemy lines (reflecting the recent British bombing of Cologne, Germany in June 1942), and quickly disguise themselves as German officers. Marshalls Bommel (Dick Curtis) and Boring (Vernon Dent) then enter, and go about flirting with pretty Moronica (Larry in drag). The Stooges eventually steal enemy secrets from under the nose of the Axis marshalls, knock the marshalls cold, and evacuate quickly.