8. Nikola Tesla
wikiNot much is known about Tesla's private life as he was a very private person. What if that was because if he told people what he'd be up to, nobody would believe him? We're picturing Tesla as a contemporary of Dr. Frankenstein. It'd perhaps explain where Frankenstein got a lot of the equipment we see in his lab, especially the stuff that lets him produce electrical currents for reanimation. As Dr. Frankenstein is quite serious most of the time, we'd have Tesla as his lighter hearted contemporary to begin with. Then as he discovers more and more about the nature of Frankenstein's research, he could become the voice of reason, warning Frankenstein of the dangers of playing God. Of course, Tesla wouldn't know about Caliban, at least not until it's too late. We're liking a guest starring role for Ralph Fiennes in the role. A big name actor playing Tesla would automatically lend importance to everything he says. In addition, Fiennes could bestow upon Tesla the level of gravitas needed to play the man supposedly responsible for creating free clean energy before his death took his idea to the grave with him.