It's autumn 1925, and a killer uncannily like England's Jack the Ripper is stalking the streets of Paris and preying on young women.

Michael Ward is a journalist newly arrived to the Left Bank. When he falls in with Jason Waddington, an expatriate American writer who introduces him to the café scene and his crowd of writers and artists, Ward soon discovers that Jack de Paris is not the only trouble afoot in the City of Light. Rumor has it that Waddington has written a damaging roman à clef about his friends, and tempers are rising as fear of the killer grips the city.

When the body of Laure Duclos is found, it seems their circle has finally been touched by Jack. But Ward has his doubts and begins to wonder whether Laure was truly Jack de Paris's latest victim or if someone else was using the serial killer as a convenient cover to protect themselves.