The inventor Svensson invents all kind of things and one of his latest inventions is a machine whicn can control an airplane from the ground through radio waves. He is friends with the great Swedish/American aviator Smith, who may be interested in testing Fridolf's machine if he can get Smith discharged from the military service, because he wants to spend more time with his fiancé. But instead Svensson is mistaken for being Smith, and suddenly he is in the military where he gets in all kinds of trouble with his superiors and also falls in loves with his sergeant major's girlfriend.