Set in Nice, it tells the story of a police detective faced with a series of unexplained killings of apparently unconnected people by a mystery sniper.

Any thoughts of taking up with her again are put aside because he has to investigate the assassination by a single shot from a long-range 0.22 rifle of Forest, a prominent local businessman.

She reveals to Carella that the end of run party degenerated into a mass sex orgy and that when Juliette, the other unknown woman, refused to join in she was gang raped.

The screenplay was adapted by Philippe Labro, Jacques Lanzmann, and Vincenzo Labella, from Ten Plus One, a police procedural novel by Ed McBain.

TV Guide called it "a deft thriller in the hardboiled tradition of Raymond Chandler and Dashiell Hammett", and said that "Labro slowly builds up a feeling of impending doom, holding the mystery's solution until the very end and maintaining a consistent mood.