The story evolves around a radio panel game show "Twenty Questions." The panel is challenged with an anonymous question. The answer leads to a series of murders in which the killer uses the programme to name his victims in advance. Two reporters spot a link between them and enlist the aid of the panel in trapping the guilty party.
Robert Beatty
as Bob Beacham
Rona Anderson
as Mary Game
Clifford Evans
as Tom Harmon
Edward Lexy
as Det. Insp. Charlton
Olga Lindo
as Olive Tavy
Daphne Padel
as Self - The Twenty Questions Team
Jeanne De Casalis
as Self - The Twenty Questions Team guest artiste
Jack Train
as Self - The Twenty Questions Team
Stewart MacPherson
as Self - The Twenty Questions Team
Norman Hackforth
as Self - The Twenty Questions Team 'Mystery Voice'
Richard Dimbleby
as Self - The Twenty Questions Team
Harold Scott
as Maurice Emery KC
