England, World War II. Quint Munroe, RAF officer and new leader of a Mosquito squadron, is tasked with destroying a secret Nazi base in France while trying to overcome the disappearance of a brother-in-arms.

The stooges are auto mechanics working for the R.A.F. in England. After wrecking an officers car they need a place to hide, but their choice, a sewer pipe, turns out to a bomb which is dropped on the enemy. Finding themselves behind enemy lines, Moe and Curly disguise as German officers and Larry dresses as a seductive fraulein. While general Bommel chases after Larry, Moe and Curly steal the secret plans from the high command.