While Plan 9 from Outer Space is often considered to be Bela Lugosi's last film, considering that movie consisted of test scenes meant for a different movie, the actual final picture of which Lugosi actively participated in should actually be this one. He plays a mute butler who doesn't really do much but still has somewhat of a presence and is nothing to be ashamed about. He is joined here by fellow horror stalwarts John Carradine (gloriously hammy here), Lon Chaney, Jr., and fellow Ed Wood-directed series castmate Tor Johnson. The star is Basil Rathbone as a mad doctor who performs brain surgeries because of a secret I don't want to reveal here. Herbert Rudley is his reluctant assistant and Patricia Blair (or Blake as she's credited here) is the daughter of Chaney who plays another mute who was once a functioning human being. There's also an amusing performance by Akim Tamiroff as another associate of Rathbone's. Other cast members worth noting: Phyllis Stanley as Rathbone's nurse, Sally Yarnell as another of the underground "patients", Claire Carleton as a "customer" of Tamiroff's, and John Sheffield as a Scotland Yard detective investigating the whole thing. I thought this was a very effective chiller that was underrated considering the cast. So on that note, I'm recommending The Black Sleep.