More a direct sequel to the "Wolf Man" with Frankenstein added in for good measure in the last moments. This one is probably the best "monster smash up" of all time at least because it is good acted by Chaney Jr as Wolf Man, has great atmosphere and a good (if brief) climax.
Not good, not bad, not horrible. It works as a good Wolf Man sequel, but as soon as the Frankenstein elements are introduced everything goes downhill fast. In the end, not very memorable. Lugosi's Creature is not good at all and this is with his role being cut down and silenced.