Orville, the oldest orphan at the Hideaway Orphans Home, accidentally hides inside a truck headed to a top-secret laboratory. There he is placed under the supervision of lab worker Lester to help load supplies onto an experimental rocket ship. While on board with Lester, Orville flips the ignition switch and the rocket ship blasts off, flying across the country and eventually landing outside of New Orleans, where Mardi Gras is in progress. Lester and Orville, believing that they have successfully landed on Mars, don spacesuits and go into the city, where they assume the grotesquely costumed celebrants are Martians, while the others assume they are fellow costumed celebrants. In time, they may not realize their mistake, but they do realize that the place they have landed in is in need of saving!