Following in the massive footsteps of the phenomenal "Frankenstein" and "Bride of Frankenstein", "Son" starts off strong with introduction of Doctor Frankenstein's son, Baron Wolf Von Frankenstein (Basil Rathbone) returning to the ancestral Frankenstein castle with his wife and son Peter. The locals treat Frankenstein with resentment at the havoc his father's monster caused, and even Frankenstein's sole friend amongst the village, Inspector Krough (Lionel Atwill) warns him stay about from his father's work. The castle setting is firmly rooted in German Expressionism with its with distorted features and crooked cast shadows. Regrettably, unintended comedy soon comes into play with Basil Rathbone's maniac performance that switches moods at the drop of a hat and his son who has an unfortunate haircut that looks like he's wearing a dead raccoon on his head. There is also a scene in the dining room that is supposed to be charming, but is lost as there is a sculpture of a boars head just above Frankenstein, the tusks just barely missing his head. Inspector Krogh seems to take the cake in the opening act as he introduces his manaical arm, which he must raise and lower manually, inhibiting us from taking him seriously. The Inspector also exposits that the monster has been sighted, causing victims hearts to burst from shear fright, which doesn't match up to what we've seen in the past two films.
Frankenstein soon encounters Ygor (Bela Lugosi), a demented man, who was sentenced to the gallows, but freed when his neck didn't break and is now a hunchback. Ygor leads Frankenstein the resting place of the now comatose monster (played one last time by Boris Karloff). Here Ygor utters one of the strangest sentences in movie history when he addresses the monster's stiff body; "He is my friend. He does things for me." Okay... Frankenstein decides to revive the monster in order to restore his father's honor. After all, what could go wrong with that plan?
The real travesty at this point is that that the so-called "stars" of the movie (Karloff and Rathbone) take a back seat to a secondary character like Ygor. Bela Legosi serves as the heavy in this feature, taking up more than twice the time on screen than that of his long time rival Boris Karloff. It would have been better had Karloff not returned as the monster for this picture, as his performance is a giant step backward. In the first two films the monster was the star, his innocent nature contrasted with his gruesome appearance and the violent situations he found himself in. Now, all of that character has been syphoned away and he has been reduced to a mute brute who does Ygor's dirty work, knocking off the people who sentenced him in a half baked revenge scheme. All the while, the monster is building up a body count and Krogh suspects Frankenstein has resurrected the monster, but Rathbone's character keeps making excuses that not even a child would believe for a minute.
There has been very little plot running throughout the film and it leads to a very unsatisfying climax involving the monster turning on Frankenstein by abducting his son. The day is saved when Rathbone's stunt double swings over a pit of molten metal to catch Peter and knock the monster in the pit. I'm rather disappointed we didn't see any buildings burn down like the last two movies. Frankenstein and family leave the village and are bid goodbye by the villagers.
While there are something interesting visuals the whole thing is ill conceived, the characters are devoid of anything interesting and the camp cancels out any potential drama and is probably best remembered as the basis for Mel Brook's spoof "Young Frankenstein".
Two and a half out of Five. Sub-Par.