In 1938 Los Angeles, pilot Cliff Secord crashes his airplane after being struck in the air in a shootout between gangsters and FBI agents in a car chase. Completely broken, his best friend and mechanic A. "Peevy" Peabody attempts to repair a broken down biplane to raise some money in an exhibition show. However, Cliff finds a package hidden by one of the gangsters with a rocket with belts and they find that the device allows a man to fly. Meanwhile, his beloved girlfriend and aspiring actress Jenny Blake succeeds in an audition to make a small role in a movie of the great actor Neville Sinclair who is ranked third at the box-office. During a flight exhibition, the mechanic Malcolm Jones has an accident, and Cliff uses the rocket to save him, being called the Rocketeer by the public. With his picture in the front page of the newspaper, Cliff is chased by the FBI, the gangsters and Nazi agents that abduct Jenny and forces Cliff to rescue her.