Boris Karloff returns for another round as the monster in Son of Frankenstein, but he isn't the creepiest role in the film. That would have to go to Bela Lugosi.
Son of Frankenstein tells the tale of Dr. Frankenstein's son (Basil Rathbone) taking over the castle of his late father. The townspeople are on pins a needles for fear that he'll be just like the old man and, of course, he is by reviving the long lost monster with the help of Igor (Bela Lugosi).
Karloff is a weird monster in this film. he has lost the ability to talk and wears a fur coat which I don't understand. He's really only going through the motions and is nowhere near the greatness that he was in the first two films. Lugosi, on the other hand, is creepy as hell as Igor, an old grave robber who had been hung for his crimes and now stalks around with a broken neck. He is the creepiest part of the film.
Though not as good as the original two, Son of Frankenstein offers a good follow-up to the tale that is light years ahaead of some of the later efforts.