A steps out onto a stage and looks directly into the camera as he informs us the producer of the movie, Carl Laemmle, thinks it unkind to show the film without warning of its ability to thrill, shock and even horrify the viewer. After urging those who may suffer ill effects to take precautions, he reminds them that they were warned.
Gravestones seen through a foggy evening indicate the macabre nature of events taking place. Dr. Henry Frankenstein and his hunchbacked assistant Fritz are in the graveyard not to pay respects to the spirits of the departed, but to steal body parts. They find a body, but the neck has been broken making the brain useless. The search must continue for a brain that works.
A university lecturer is showing off a perfect specimen of a brain to his students. Dr. Waldman is Frankenstein’s old college professor and he is getting a visit from Elizabeth, Henry’s fiancé, and their friend Victor Moritz. Elizabeth has sought out the doctor to share her concerns about Henry’s strange experiments with creating life and his growing obsessiveness.
Frankenstein and Fritz are making preparations in his lab to experiment with giving the spark of life to tissue which is dead when they are interrupted by the arrival of Waldman and Elizabeth. On the verge of madness, Frankenstein beseeches them to watch as he proves he has discovered the secret to bringing life into the world. The dead body is raised high through an opening in the roof of the lab and exposed to the raging lightning storm. His machines whirr, crackle and light up. A loud crash of thunder precedes the miraculous sight of the hand of the dead body beginning to move with life. Frankenstein seems to perch very precariously over the precipice of madness as his excitement at possibility of success transforms into outright mania at the realization of success. He almost collapses as he shouts that his creature is alive.
The first tentative moments with the reanimated body reveals its grotesque appearance is accompanied by a childlike lack of development. When he asks the creature to sit, however, it does so. When he reels back the opening in the roof and bright sunlight pours into the dark, dank room, the creature reaches his hands out as if to touch the light bringing the warmth. Fritz suddenly enters carrying a torch and the monster recoils in fear at the sight. Upon returning with Waldman, Frankenstein mistakes the reaction for a violent attack against them, however, and the next time the creature appears he is a prisoner locked in chains deep in the dungeon. The two doctors have quickly diagnosed Frankenstein’s creation as being unfit to live among society.
Left alone with the pitiful creature, Fritz uses its fear of fire as a tool to torture him with the torch. From above, Frankenstein and Waldman hear a piercing shriek and rush to discover that the monster has strangled Fritz. He lunges threatening toward them, but they manage to escape his wrath and prepare a sedative injection. Upon success, the creature drops to the floor.
Henry is preparing for wedding as Waldman examines the creature for dissection. When he turns his back, the creature comes up behind him and strangles him, escaping out of the tower and into the wilderness beyond. His first encounter with other humans is a pretty young girl playing by the lakeside. She is unafraid despite his appearance and invites him to sit and play with her. They play a game of tossing flowers onto the surface of the nearby water and watching them dance atop the water as they float. When they run out of flowers, the creatures decides to continue the game by tossing Maria into the water to watch her float. Maria does not float, however, nor does she swim. Instead she drowns. The monster is traumatized by this unexpected occurrence and runs away.
Frankenstein and Elizabeth are waiting only for Dr. Waldman’s arrival to get married. Suddenly, Victor swoops in, breathless, with the news that Waldman has been murdered. A loud scream from another part of the house confirms his suspicion that the creature is responsible. A search only turns up an unconscious Elizabeth, however, with no sign of her attacker.
Maria’s father walks into town, carrying his daughter’s lifeless body and claiming she was murdered. A group of townsfolk form to hunt down and capture the monster that committed this horrific act. They split into three groups with Frankenstein heading up the one that heads into the mountains. During the search, he gets separated from the others and is attacked by the creature which knocks him out and carries him up to an old mill. As he comes to and starts to cry out, the other members of the search party hear the sound and follow it. The give chase and the creature climbs to the top of the mill with Frankenstein as his prisoner. The torches carried by some of the townspeople sends the creature into a rage and he suddenly throws Frankenstein over the side where his fall is partially broken by bouncing off the slowly rotating vanes of the windmill. While some villagers transport Frankenstein to safety while the others move to set fire to the mill now that creature has trapped himself at the top with nowhere to go.
Later, back at Castle Frankenstein, Henry’s father offers a toast to the future birth of his grandson now that his son has recovered and been married to Elizabeth.
