The film follows Theodore Honey (James Stewart), a highly eccentric "boffin" with the Royal Aircraft Establishment. A widower with a precocious young daughter, Elspeth, Honey is sent from Farnborough to investigate the crash of a "Reindeer" airliner in Labrador, which he theorizes occurred because of a structural failure in the tail caused by sudden metal fatigue. To test his theory in his laboratory, an airframe is continuously shaken in eight-hour daily cycles.
