In 19th century London, Dr. Charles Marlowe experiments with a mind-altering drug which causes him to develop an evil alter ego, Edward Blake, whom his colleague begins to suspect is someone that is blackmailing Marlowe.
Christopher Lee
Peter Cushing
Mike Raven
Richard Hurndall
George Merritt
Kenneth J. Warren
Susan Jameson
Marjie Lawrence
Aimée Delamain
Michael Des Barres
Ian McCulloch
Chloe Franks