When author Charles Regnier returns to Paris with a best-selling book that criticizes the government, he's tormented by frequent blackouts. After a mysterious cat-like creature slaughters people close to him, Charles is suspected of murder. Charles fears that he is the beast, but his paramour Marie and best friend Henry, believe he's innocent... until the creature begins to stalk Marie.
There is a scene in this film when "Marie" (Leonor Aubert) is in a coach, terrified, with the protagonist in this Jekyllian style thriller. She is shouting, pleading, imploring with this person - who transmorphs into a deadly cat - for him not to kill her. When she calls out for him to "say something to me" the entire cinema - maybe 50 people, all simultaneously called out "miaow". It was really an achievement of coordination and comedy timing that far surpassed anything creative being seen on the screen as this rather dreary murder mystery rubbed along. Carl Esmond is "Regnier", a successful novelist who discovers that his book is going to be censored. When the archivist carrying papers to the censor is found dead - mauled - he is suspected and off we trot on the most benign of mysteries that lacks just about everything - except, perhaps, an alluring eeriness of late 19th century Paris. The writing, directing and acting are wholly adequate, but the thing lacks any sense of menace or thrill - and at times it is little better than a darkly lit romance with a well telegraphed twist.