I'm not entirely sure how I feel about this audio drama. Is it a faithful adaptation of the original Frankenstein? Not really. In many ways it hews much closer than a lot of the film adaptations, but in many other ways it's ridiculously different. I feel like there's a certain influence from Curse of Frankenstein, and quite possibly other adaptations I haven't yet encountered. Whereas I find both creator and creature sympathetic in the original, here both Frankenstein and his monster are massive assholes - as is practically everyone else, except for Victor's dad, best friend, and wife. Some of the changes are things I liked. The idea of the monster's brain coming from Waldman is an interesting one, and while the way Waldman acts as a Faustian mentor isn't in the original text, it's a neat way of giving Victor the obligatory adaptational assistant. On the other hand, Waldman's brain in the body changes nothing about the monster's behavior (unlike, say, Ghost of Frankenstein). I also like seeing more of Captain Walton as intercutting the frame narrative throughout helps make it more relevant. I feel similarly about giving the monster and Victor more chances to interact.
On the other hand, aside from the aforementioned assholeness of the characters, there's a lot of stuff that's kinda weird and not necessarily well done. The monster gets his say, unlike many of the adaptations of the novel, but here it's somewhat abbreviated, with no mention of the books he read and the process of learning language, which I feel are key parts of his character. I understand cutting down on the DeLacey subplot due to time constraints, but I don't like having the monster murder them all. I also didn't much care for the other enhanced moments of violence on the monster's part. And some of the subplots and bits that are added in, like Victor being in love with Justine rather than Elizabeth, just highlight how awful he is.
I understand that some of the changes are the scriptwriter's interpretations of the novel, but I strongly disagree with these interpretations. I think I find myself especially frustrated by some of the changes here because this audio does a good job of adapting things to some extent, and then veers off into crazy territory. It's more disappointing to be let down by what seems to be a faithful version than to see the craziness of yet another goofy movie. In fact, I think maybe I'd've enjoyed this more if it had been more upfront about it's divergences, or if the narrative had truly embraced the changes it makes and follow them through to a new story. Of course, perhaps it does that somewhat through it's rather bleak ending, but still, I'm not I feel it does well enough to tell a good story rather than being lost between faithful adaptation and entertaining riff.
On the plus side, the production values and acting talent on display here are quite good. There's a lot of nice special effects work and the dialogue's nods to the necessity of describing what characters see because we the audience can't see anything never felt especially awkward. Arthur Darvill is a genius choice for the role of Victor, and it's a lot of fun to see him as a villain after experiencing his heroic side in Doctor Who and Legends of Tomorrow. Nicholas Briggs is, of course, the obvious choice for the monster, and I generally like how he portrays the monster's voice. As he says in the interviews after the production proper, he felt it important to mark the monster as monstrous somehow, and in the audio medium voice is the obvious way to go. Speaking of, the edition I bought from Audible appears to be the Special Edition of this audio, and it includes the complete score as well as an hour or so long documentary about the making of the story. There's plenty of interviews with the cast and crew, including discussions of their favorite horror stories and any paranormal experiences they may have had. I was hoping to get some recommendations for other horror audio stuff to check out, but sadly that didn't happen. Still, the documentary is pretty neat, though I'm not sure how useful the score is in Audible format.
I did have fun listening to this, and it's definitely whetted my appetite for more audio dramas, especially those done by Big Finish. I think maybe if I listen to this again and keep in mind that it is its own story and only moderately more faithful to the original than most films, I may have more fun with it. Certainly, I didn't have a terrible time with this audio drama, but I do sorta wish it had been able to follow up on its own ideas more. Perhaps its like how I enjoyed the prequel and sequel to Pride and Prejudice and Zombies much more than the original because they could use the classic characters but create new and interesting plots. Also, I think it's a little hard for me to really love an adaptation that goes so far to make everybody an awful person, since part of what's interesting about Frankenstein and many other adaptations is how there's some degree of moral ambiguity to Victor and his creature. All in all, this was a nice if sometimes disappointing way to spend a few hours, and I'll certainly get other Big Finish Classics, though I'll be sure to keep in mind that they won't be especially accurate to the originals.