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Hiddleston first started portraying Loki in the MCU in 2011 when he appeared in the first Thor movie. He has since reprised the role in several other films in the MCU, including The Avengers, Thor: The Dark World, Avengers: Age of Ultron, Thor: Ragnarok, and Avengers: Infinity War. He is set to return to the role in the upcoming film Avengers: Endgame.