In foggy London Dr Jekyll experiments on newly deceased women determined to discover an elixir for immortal life. Success enables his spectacular transformation into the beautiful but psychotic Sister Hyde who stalks the dark alleys of Whitechapel for young, innocent, female victims, ensuring continuation of the bloodstained research. With each transformation Sister Hyde becomes the more dominant personality, determined to eventually suppress the frail, ineffectual Dr Jekyll forever.
Ralph Bates
as Dr. Jekyll
Martine Beswick
as Sister Hyde
Gerald Sim
as Professor Robertson
Lewis Fiander
as Howard
Susan Brodrick
as Susan
Dorothy Alison
as Mrs. Spencer
Ivor Dean
as Burke
Philip Madoc
as Byker
Irene Bradshaw
as Yvonne
Neil Wilson
as Older Policeman
Paul Whitsun-Jones
as Sergeant Danvers
Tony Calvin
as Hare
