This was probably my introduction to a lot of things- horror comedy, Boris Karloff, Peter Lorre and Vincent Price all at once. As a kid seeing this I had no idea what it would be about. It's one of my favorite movies, and I'm still sure Doctor Stephen Strange's look was patterned after Vincent Price, though perhaps not from this movie, since the timing would have been amazing.
It's got a clever screenplay and some great adlibbed lines from Lorre, which apparently bother Karloff at times. I kind of wish the budget had been a bit bigger to include some animated spells being cast, but overall one really can't complain. Oh, and I think that Nicholson kid might have a career as an actor some day.