Eight people - five men and three women - gather at a country mansion, 'Monskwell Manor', run by a young couple, Molly and Giles Ralston.
A few days of mental calm and carefree await them... At least, that's what they all believe. However, they will quickly realize that a ruthless murderer has infiltrated among them, who has already killed someone in London. Mrs. Lyon was his first victim.
And now, at this very moment, this man, slowly and methodically, is preparing a second... Maybe even a third murder, with the unparalleled ability of a man whose exceptional intelligence is driven by a morbid desire for revenge.
The snow, falling incessantly all around the mansion, creates an impenetrable trap around the trapped individuals, favoring his dark plans wonderfully. No one can escape. Detective Trotter will try a bunch of clever tricks to trap the killer, but this satanic man knows how to slip away... The macabre motif, the 'Three Blind Mice', will constantly accompany, like a nightmarish background, the scene of horror! Where will the evil stop and which hand is spreading death? Which of all the faces is not the one it claims to be, but the dark origin of evil?