A man is murdered in a room with no windows and a steel lined door which locks only from the inside.

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Main Cast: Bernard Lee, David Knight, Francis de Wolff, Colette Wilde, Christine Shaw, Stanley Morgan, A.J. Brown, Richard Caldicot, Edmond Bennett, Simon Lack

Director: Allan Davis

Writer: Philip Mackie

Editor: Bernard Gribble

Cinematographer: Brian Rhodes

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