Orphaned identical twin sisters go to live with their fanatical, witch-hunting Puritan uncle, and while one falls for the local schoolteacher, the other is seduced and turned into a vampire by a decadent count dabbling in black magic. The uncle's vigilante brotherhood ultimately storms the count's castle to end the horror. Hammer Films production starring Peter Cushing, notable for casting real-life twins Mary and Madeleine Collinson.