The story begins with Captain Robert Walton hanging out in St. Petersburg, Russia, probably near the end of the 18th century. He's waiting around for a ride to the port of Archangel, where he's going to hire some hardy Russians to go sailing off to the North Pole. Unfortunately, the boat gets stuck in impassible ice hundreds of miles from land. Boring! With nothing else to do, he writes letters to his sister back in England. His main complaint? He wants a male friend to keep him company. (What about that ship full of sailors? No, he means a worthy companion.)
Soon, Walton's despair is interrupted by the sight of —a man! On the ice! Riding a dog-sled! The man boards the ship, and it seems as if Walton's wish for a friend has come true. Except this new guy, Victor? Kind of nuts. Here's his story, as told to Walton:

Victor started out like any normal kid in Geneva, with his parents adopting a girl named Elizabeth for him to marry when he was older. You know, totally normal. At college, he decides to study natural philosophy (like a rudimentary physics) and chemistry, along with chemistry's evil twin, alchemy. In about two years, he figures out how to bring a body made of human corpse pieces to life. (We couldn't even manage to finish high school in two years.) Afterwards, he's horrified by his own creation (no…really?) and is sick for months while his friend Henry Clerval nurses him back to health.