With its history of murder and suicide, the affluent Hammond family is seemingly cursed. When deaths on the British clan's estate draw the involvement of Scotland Yard, investigator Bob Curtis (James Ellison) arrives to look into the mysterious matter. Oliver Hammond (John Howard) and his sister, Helga (Heather Angel), are among the relatives who must contend their family's dark secret, which involves the legend of a werewolf. Can the macabre legacy of the Hammonds be stopped?