Following the brutal death of a prostitute at an exclusive Parisian brothel, grizzled Inspector Fontaine is brought in to investigate. After implicating Antoine, a petty thief and regular client of the murdered woman, Fontaine believes the case to be closed. However, Antoine makes a daring attempt to escape custody, only to get decapitated in the process, after which his eyes are given over to strange Professor Waldemar for study. But soon enough those affiliated with implicating him begin to meet their own violent ends. Has Antoine's vengeful spirit returned to kill those he believes responsible for his own gruesome fate? Or has another, more sinister character been behind these diabolical murders from the very beginning?