William Frankenstein funniest character in the film tbh. Definitely best poised to experience the true horror of the story. Like, his defining characteristics are "normal" and "pleasant".
His dad and his brother are both weird, obsessive surgeons, but he works in finance. He gets engaged to a beautiful woman and maybe he doesn't even notice that she's also really weird, because he grew up around it. (Or maybe he doesn't care bc her family has money lol) Seemingly either doesn't notice or doesn't care that his brother becomes instantly infatuated with his fiancée.
He's actually pretty smart about medical stuff, but nobody cares because his brother's a mad genius. He somehow gets roped into being the project manager for the renovation of Victor's Ethically Dubious Laboratory, and he does a really good job, and doesn't ask any probing questions or complain at all! He doesn't even say, "hey Victor it's kinda fucked up that you're doing weird craft projects with random corpses."
Endlessly supportive of Victor, even when he is doing objectively crazy shit. Victor presents him with the dead body of William's uncle-in-law, who is also their friend and benefactor, and William has GOT to be thinking, "there's a VERY good chance my brother had a hand in this man's death, but there are no other witnesses around, then or now." So William's just like, "wow that sucks Victor, you're so right, this place is too dangerous for me and Elizabeth!" (we won't get into who MADE it dangerous!)
He's probably more than happy to take Victor's suggestion to flee his lab, but then they're in the car and his GIRLFRIEND is like, "turn around right now or I'm throwing myself out onto the street. Your brother's going to kill the person he made and we have to stop him." So William's like, "fuck, ALRIGHT, i guess!!!" even though at this point he kinda wants to stay as far away from his brother and the person he made as possible, but he doesn't want his girlfriend to throw herself out of a moving vehicle. And they do turn around and his brother has literally blown up the whole building and shattered one of his own legs.
William literally worked really hard on that renovation, but whatever! There's no sign of the person Victor made, and William is absolutely Not Going To Ask.
William takes Victor in and takes care of him, and he seems a lot more normal now, which could just be the combination of pain and pain medications, but whatever. Things are actually not really about Victor right now, because William and Elizabeth are finally getting married!! There are so many fucking flower petals. I bet William was so hype to be a husband and have a family and all that normal shit. (even if it was with a wife who won't stop talking about how war profiteering is "wrong" or whatever 🙄)
Alas. The seven-foot-tall HUMAN PERSON his older brother MADE FROM DEAD BODIES is at the wedding venue. Somehow. (literally not even invited.) It's beating his brother up and breaking shit. William's bride has been murdered. WILLIAM has been murdered. He uses his dying breath to tell his brother that he fucking sucks. (correct)