The stooges are dressed as Japanese soldiers for their job as magazine models. On their lunch break they go into a restaurant with their Japanese uniforms on causing the proprietor to mistake them for the real thing, and a chase ensues. The boys fall through a trap door, and into a nest of Nazi spies where they are mistaken for "Naki", "Saki" and "Waki", three Japanese saboteurs. The stooges try to act the part, including demonstrating acrobatics and jiu-jitsu to their hosts. When the real "Naki", "Saki" and "Waki" show up, the boys are exposed and impostors, but after a wild fight manage to capture all the Axis spies.
You'll Go Slap-Happy When the Stooges Go Jap-Happy!
The acrobatic act was part of the Stooges stage show for many years before they started their film career.