Several murders have been committed in a London park and the victims have been savagely clawed about the throat. The police believe that a woman is a killer, and perhaps she is a (she) werewolf. Heiress Phyllis Allenby, fears she is the criminal, based on the family legend of the "Allenby Curse" which was the belief that members of the family at times assumed the form of a wolf. Her aunt's constant reminders to her of the "Allenby Curse" only serves to keep her niece's fears alive.