The movie I, Frankenstein is a fantasy action film that follows the story of Adam, the creature created by Dr. Frankenstein two centuries ago. After living in isolation, Adam finds himself drawn into a battle between two immortal clans, the Gargoyles and the Demons, who have been fighting for centuries over the fate of humanity.
Adam learns that he possesses an important secret that could tip the balance of power in the war. The Demons are determined to capture him while the Gargoyles, led by Queen Leonore, want to protect him and keep him safe. Along with a band of Gargoyles led by Ophir, Adam sets out to save humanity from the evil forces of the Demon Prince Naberius, who plans to use Adam's secret to create an army of reanimated corpses to conquer the world.
With the help of Gideon, the leader of the Demons, who turns out to be a former ally of the Gargoyles, Adam unites the two clans to fight against Naberius and his army of demons. The battle takes place in the city of New Orleans, where the fate of humanity hangs in the balance.
During the final fight, Adam faces off against Naberius and his army of reanimated corpses, using his immense strength and durability to defeat them. In the ultimate showdown, Adam sacrifices himself to destroy the portal that Naberius was using to summon his demons to Earth, ending the war and saving humanity from certain doom.
The movie concludes with Queen Leonore acknowledging Adam's heroism and giving him a rightful place among the Gargoyles, honoring his legacy as a protector of humanity.