In the back alleys of the decadent, bohemian Montmartre, the Theatre du Grand Guignol opens its doors to an unsuspecting public. The plays performed are rife with madness and murder. Renowned psychiatrist Alfred Binet has become obsessed with the theatrical horrors on display and ingratiates himself into the company. He meets Andre De Lorde, the premiere playwright of the Grand Guignol. Binet seeks to unlock the answers to De Lorde’s fascination with death and psychological trauma, but in doing so he inadvertently becomes the writer’s new muse. Soon, the Grand Guignol is a huge success.

But things become complicated when a serial killer known as The Monster of Montmartre begins spilling blood on the streets, and De Lorde reveals his previous collaborator was none other than the ghost of Edgar Allan Poe… Soon, Binet begins to lose his grip on what is real and what isn’t, as the boundaries between the world of the Grand Guignol and reality begin to blur…