Marc Elbichon, a novice private sleuth, is investigating a wave of assassinations bearing a particular characteristic: the perpetrator, dubbed the "telephone killer" always strangles his female victims with a telephone cord.

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Main Cast: Didier Bourdon, Bernard Campan, Pascal Légitimus, Smaïn, Seymour Brussel, Jean-Claude Brialy, Clémentine Célarié, Michel Constantin, Darry Cowl, Michel Galabru

Director: Jean-Pierre Vergne

Writers: Jean-Pierre Vergne, Seymour Brussel, Bernard Campan, Pascal Légitimus, Didier Bourdon

Editor: Nicole Berckmans

Cinematographer: Robert Fraisse

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