Nick Carter boards an airliner with John Keller, the inventor of a revolutionary new aircraft. The pilot makes an unscheduled landing so that his confederates can try to steal Keller's plans, but Carter holds them off, and stewardess Lou Farnsby manages to fly them to safety. Carter, posing as "Robert Chalmers", the new assistant to Hiram Streeter, the boss of the California factory, has Lou reassigned to the infirmary.