 While covering a flight of the US Air Force s X-15 rocket plane, newspaper reporter Tim O Hara finds a crashed alien spaceship that contains one live martian, a kindly professor that specializes in the Earth s backwards culture. The martian can levitate things, read minds and disappear when he raises his antennas. Not wanting to be discovered by the authorities, he assumes the identity of Tim s Uncle Martin and begins to repair his spaceship so that he can return to Mars.