Mystery Plane (aka Sky Pilot and Sky Pirate) is a 1939 American action film directed by George Waggner and written by Paul Schofield and George Waggner. The film is based on the comic strip Tailspin Tommy by Hal Forrest and Glenn Chaffin. The film stars John Trent, Marjorie Reynolds, Milburn Stone, Jason Robards Sr., George Lynn and Lucien Littlefield. Mystery Plane, the first of four "Tailspin Tommy" films made by Monogram Pictures, was released on March 8, 1939. Plot In the fall of 1923, young Tommy Tomkins (Tommy Bupp) admires Captain Brandy Rand (George Lynn), a World War I ace. Brandy flies in and parachutes out of his aircraft, but lands in a lake. Tommy rescues him in a rowboat, then shows Brandy a scrapbook about the flyer's exploits, who encourages the young man to become a flyer himself. Many years later, Tommy (John Trent) becomes a pilot and is managing an airport in Shreveport, Louisiana. He designs a radio-controlled bombing device that Tommy and his partner Skeeter Milligan (Milburn Stone) are ready to demonstrate to the Army. The Army commander (John Elliott) is very impressed when they score two direct hits. A gang of spies is also watching the test. The spies, who include a much-weathered Brandy, now a drunk running contraband, have been offered half a million dollars for the device from an enemy country. Another spy, Anita (Polly Ann Young), asks to take flying lessons from Tommy as a means of watching him and his operation. When he is tricked by a fake message, Tommy is captured by the spies. As he is being interrogated, a drunk and chagrined Brandy comes into the room. The spies then take Skeeter and Tommy's girl friend, Betty Lou Barnes (Marjorie Reynolds), hostage to force Tommy to give them the plans to the bombing device. Tommy, Skeeter and Betty Lou manage to escape in a biplane. A troop of Army soldiers arrive at the hideout and arrest Anita, while the other spies flee and pursue Tommy in Brandy's aircraft. Brandy, however, radios Tommy to change course and then crashes his aircraft into the ocean. When the spies are captured, a squadron of Army aircraft equipped with the new bombing device become part of a film shot at Shreveport. Tommy, Betty Lou and Skeeter all laugh at the prospect of "Tailspin Tommy" appearing on the silver screen. Cast John Trent as Tailspin