The red night was set within the space of a few hours and in two locations - the rich madam Lesparre's old castle (where celebrations are underway to mark the marriage of her daughter Ginette to the handsome Robert) and the sinister mill 'Moulin-Maudit'. The young couple leave to their honeymoon driven by a mysterious chauffeur. Following a breakdown in open country they are forced to seek refuge in the mill, where untold horrors wait: blood oozing from the ceiling, a body wrapped in a tarpaulin, a menacing dumb figure and an old woman, etc.