He loves it all so much that he's built a hidden torture chamber in his house filled with torture machines suggested by Poe's short stories and poems. He keeps stuffed ravens everywhere. And he loves quoting Poe. The nine-hundred writers who worked on this hour-long movie really went all out in the 'Inspired by Edgar Allan Poe' department.
There's even a modern-dance sequence that interprets Poe's poem "The Raven." They don't make horror movies like this any more.
Lugosi's Dr. Vollin becomes obsessed with the young dancer he saves with his surgical skill. With the unwilling help of escaped murderer Karloff (who gets the more sympathetic role here), he intends to revenge himself on everyone who's wronged him in the first fifteen minutes of the movie. Much hilarity and scenery-chewing ensues, along with some woeful comic relief, some ingenious death traps and hidden rooms (and rooms with hidden properties), and one of Karloff's subtlest performances.
As a strange bonus, Karloff's character ends up looking a lot like the inspiration for the Batman villain Two-Face, just as the protagonist of an earlier horror movie, The Man Who Laughs, is the spitting image of The Joker. Recommended.