Dr. Daniel Challis and Ellie Grimbridge stumble onto a gruesome murder scheme when Ellie’s novelty-salesman father, Harry, is killed while in possession of a strange mask made by the Silver Shamrock mask company. The company’s owner, Conal Cochran, wants to return Halloween to its darker roots using his masks — and his unspeakable scheme would unleash death and destruction across the country.

Two aging film actresses live as virtual recluses in an old Hollywood mansion. Jane Hudson, a successful child star, cares for her crippled sister Blanche, whose career in later years eclipsed that of Jane. Now the two live together, their relationship affected by simmering subconscious thoughts of mutual envy, hate and revenge.