Creator Backlash: Frank Darabont has said in interviews that he was displeased with the finished film, feeling that Kenneth Branagh had mishandled the project.
Deleted Role: Fay Ripley filmed a small role, she was bitten by the Creature, but her scenes never made the final cut.
Deleted Scene: Other scenes were shot confirming that Henry is left alive at the end of the film, but they were cut. Henry's fate is left ambiguous, last seen as Victor flees his burning house.
Doing It for the Art: Branagh and De Niro thought that the Creature should have mismatched legs and spent hours trying out different types of footwear to get the proper limp. Also, the Creature's birth scene required a full body prothesis and De Niro had to come in at two in the morning and stay absolutely still as a team of makeup artists meticulously stitched him into the suit.
Star-Derailing Role: This movie put the brakes on Branagh's career as a mainstream actor and director. He didn't mind too much though, as he preferred theatre and indie projects that brought him critical acclaim. It did, however, make it hard for him to put together funding for his Hamlet passion project. It wasn't until the 2010's and his helming of Thor that he began being offered blockbuster projects again.
Fred Saberhagen, who wrote the novelization for Bram Stoker's Dracula, allegedly tried to get the novelization job for this film as well just so it could say "Mary Shelley's Frankenstein: from the author of Bram Stoker's Dracula" on the cover.
Kate Winslet lobbied very hard for the role of Elizabeth. Although it went to Helena Bonham Carter, Kenneth Branagh was impressed by her and cast her as Ophelia in his version of Hamlet. Emma Thompson was also the first choice for Elizabeth, but she had commitments to Carrington at the time.