In the circus stationed in London, there lives a young man with a hunchback since childhood (Daniel Radcliffe). His ugly appearance can only be used for fun, but the young man loves medicine alone, especially anatomy. In a performance accident, the young man used his knowledge to save the actress Lorelai (Jessica Brown Findlay) who fell and fractured her life. His knowledge was appreciated by the mad scientist Victor Frankenstein (James McAvoy), so the latter tried every means to rob it and named it Igor. Before this, Frankenstein had stolen the bodies of dead animals in the zoo, and his series of practices were only for a crazy and bold experiment, that is, to create artificial creatures by patching up. The crazy journey begins...