When a series of murders with religious motifs occurs, a police detective must unravel the mystery and catch the killer before they strike again. As he delves deeper into the investigation, he discovers a dark secret that leads him to an apocalyptic plot.

In a small village in France, a series of brutal murders occurs. As a seasoned detective and a young ophthalmologist try to solve the case, they unravel a sinister ritual involving a demon, a nun, and a secret cult. With the body count rising and the rainstorm intensifying, they must race against time to catch the elusive serial killer before more lives are lost.