Q Planes

In 1938, advanced British aircraft prototypes carrying experimental and secret equipment are vanishing with their crews on test flights. No one can fathom why, not even spymaster Major Hammond or his sister Kay (Valerie Hobson), a newspaper reporter, who is working undercover in the works canteen used by the crews at the Barrett & Ward Aircraft Company. Tony McVane returns to the aircraft factory determined to make the next test flight. His aircraft, like the others, is brought down by a powerful ray beamed from a mysterious salvage ship.