Boris Karloff is at his unsettling, un-made up best as hansom coachman who moonlights as a graverobber, supplying doctor Henry Daniell with cadavers for the study of human anatomy and holding the illicit conspiracy over Daniell's head like a scalpel. An adaptation of a story by Robert Louis Stevenson, based on the notorious 'resurrectionists' of nineteenth century Edinburgh, the film is rich in period detail, the script literate (if wordy), with the shock value saved for the end, and well worth waiting for. British critic Robin Wood has written, "It is a marvelously constructed film, a moral fable on the subject of dehumanization carefully structured in terms of its characters--brutalized body-snatcher, experienced doctor tormented by his complicity yet too involved to extricate himself, young doctor in continual danger of getting drawn into the same trap--yet given considerable complexity by the varying play of sympathy elicited for each (Karloff's body-snatcher remains disturbingly human)" (in Film Comment, Summer '72).