Henry Creel, also known as One (001), Vecna, or the Mind Flayer, is the main antagonist of the Netflix original series Stranger Things. He will also be the main protagonist of the upcoming video game Stranger Things VR.
He is a mysterious psychic who is the son of Victor and Virginia Creel, the younger brother of Alice Creel, and the ruler of a supernatural dimension called "the Upside Down", acting as a hive mind for every entity and creature originating from it, such as the Demogorgons, Demobats and Vines. In his goal to conquer the world, he goes on a murder spree in the town of Hawkins in order to start a full-blown invasion of his world on Earth so he can destroy all human life and reshape it for himself. He is also the former friend/mentor turned archenemy of Eleven and is also the archenemy of Will Byers.
He is portrayed by Jamie Campbell Bower.