Wendy Toye directs this thriller starring John Justin as Philip Chance, a successful writer. Philip's publisher Maurice (Raymond Huntley) calls Philip back from the south of France with an invitation to write a biography of a young pilot, Martin Teckman (Michael Medwin), who was killed during a test flight in a new warplane, the Walters-Armitage F109. As Chance delves into the life of Teckman and the crash, he struggles to make sense of contradictory information. When friends and colleagues of Teckman start disappearing, Chance realises how murky the case is and begins to question the circumstances of Teckman's death.