Terror reigns at Collinwood when several patients are stabbed to death at a nearby psychiatric clinic where Barnabas Collins is a patient. Each victim’s forehead is marked with a scorpion, the zodiacal symbol of death.
Then Diana Collins, another relative of the Collins family who is undergoing psychiatric treatment at the hospital, finds a bloody knife in her room. Diana, whose astrological sign is Scorpio, is afraid that she may have committed the murders during a blackout. The fear that she is losing her mind is compounded when no one will believe she has seen a strange, wolf-like creature prowling the grounds.
The only person who will listen to her story is Barnabas. But how can he help her when he too has become a suspect?