* Paul Massie as Dr. Henry Jekyll / Mr. Edward Hyde
* Diane Cilento as Ivy Peterson
* Christopher Lee as Inspector Newcombe
* Harold Goldblatt as Mr. Peterson
* John Laurie as Mr. Stratton
* Frederick Valk as Dr. Lanyon
* Gwen Watford as Mrs. Stratton
* Victor Maddern as Inspector Blake
* Peter Cushing as Chief Inspector Newcombe
While Peter Cushing is a prominent name in horror cinema, he only had a small role in this film as the "Chief Inspector Newcombe." It is easy to see why he might be mistaken as a lead due to his prominence in horror films.