In Dijon, Inspector Hanaud investigates Betty Harlowe after her uncle, Boris Waberski, accuses her of poisoning her wealthy aunt for an inheritance. While an initial autopsy finds nothing, Hanaud discovers the use of Strophanthus Hispidus—a rare, undetectable poison applied via an antique arrow. Amidst a flurry of "poison pen" letters and deception, Hanaud proves the murder occurred despite the lack of conventional medical evidence.
Julius Hagen
Producer
Cyril Twyford
Writer
Leslie S. Hiscott
Director
Henry Edwards
Producer
Benita Hume
Betty Harlow
Richard Cooper
Jim Frobisher
Dennis Neilson-Terry
Inspector Hanaud
Stella Freeman
Ann Upcott
Wilfred Fletcher
Wabersky
Tony De Lungo
Maurice Thevene
Barbara Gott
Mrs. Harlow
Betty de Malero
Francine
