In Edinburgh in 1831, one year before the Anatomy Act was passed that expanded the legal supply of cadavers for medical research and education in reaction to public fear and revulsion of the illegal trade in corpses, a surgeon hires a cabman named John Gray (Boris Karloff) to dig up graves to provide him with fresh corpses for dissection -- but the body provider turns to murder to get new corpses for the doctor.
The frequent mentions of William Burke, William Hare, and Dr. Robert Knox, all refer to the West Port murders in 1828, a well-known series of kills where, like in this film, the doctor turned to questionable sources to get cadavers. A child's ditty immortalizes the events: "Burke's the butcher, Hare's the thief, Knox the boy who buys the beef!" This film features Bela Lugosi and Boris Karloff together, which is always a treat, though sadly their shared screen time is brief and this will be for the last time they come together. We are blessed to have the story come to us from Val Lewton, possibly the greatest horror creator of the era. His "Cat People" is a masterpiece, and this film is not ranked much lower, if at all.
Aside from the acting and directing, what really makes this film interesting is the series of dichotomies it presents. We have a need for cadavers on one hand (if doctors are to learn necessary skills) but this is balanced with the nastiness of grave robbing. If people do not provide their bodies for examination at death, what choice is left: ought we to rob the graves of freshly deceased, or ought we to allow doctors to practice blindly, possibly leading to more death? There's a backdrop discussion of social class, with the doctor's housekeeper who is secretly his wife (because he could not be known to marry below his caste). This puts the doctor in an interesting position, hiding his love from the world. We also see when he talks with Gray that he goes to Gray's lower level rather than bringing Gray up to his. The doctor is willing to submit to insult for his needs, but is not willing to decorate his seedy friends.
We see both Gray's humanity (with regards to a crippled girl) and his obvious inhumanity that comes out in his murderous spree. But, yet, as already mentioned... if the body of one person can potentially save the lives of many others, perhaps this cruel hobby is in fact a humanitarian act? One less blind girl could lead to fully meaningful lives for others. I will not make the judgment.
I owe a special debt to Peter Christensen for bringing some of these issues to my attention. While not considered a "classic" horror film on the level of many others, it remains a well-constructed piece of film, and an improvement on the story of Robert Louis Stevenson, something we do not often see.