* ExecutiveMeddling: All [[ContinuityNod the references]] to ''The Ghost of Frankenstein'' were cut, which shortened The Monster's appearances on-screen drastically. This was mostly due to a test-screening where the audience laughed at Bela Lugosi's Hungarian accent. This frankly completely changes the context of the ending, since it would have originally been Ygor/the monster as the evil one, with Talbot as the hero. Instead, its just a "poor dumb monster" fighting his new friend for flimsy reasons.
* TheOtherDarrin: Creator/BelaLugosi replaces Creator/LonChaneyJr as the Monster. In addition, Elsa Frankenstein from ''Film/TheGhostOfFrankenstein'', is played by a different actress.
* WhatCouldHaveBeen: Along with the deletion of Lugosi's lines as the Monster, Creator/LonChaneyJr, was originally set to play both monsters, but this was dropped.
* YouLookFamiliar:
** Creator/DwightFrye and Creator/LionelAtwill, who'd appeared in several earlier ''Frankenstein'' films as different characters, show up yet again here. Ditto Patric Knowles, who was Frank Andrews in the first ''[[Film/TheWolfMan1941 Wolf Man]]'' film and plays Dr. Mannering here.
** Not to mention that Bela Lugosi had played Ygor in ''Film/SonOfFrankenstein'' and ''Film/TheGhostOfFrankenstein'', as well as Bela the gypsy in ''Film/TheWolfMan1941''. Or that Lon Chaney, Jr. had played the Monster in ''Ghost''.
** And! It has Dennis Hoey playing [[InspectorLestrade an incompetent and bumbling police inspector]]. Which is exactly what he was doing in Universal's Sherlock Holmes movies being made at the same time.