With nearly two dozen films and a boatload of additional canon in the MCU thus far, you'd almost expect there to be characters you didn't know had made it to the big screen. The list of actors appearing in the MCU might seem easier to parse, numerous casting-related Easter eggs are still hiding out on the IMDb pages of the various Marvel Studios films.
Several of Marvel's best actors have secretly played more than one role in the MCU, and only the most hawk-eyed viewers have noticed. Some of the names on the list are minor players, but others are among the most prominent actors in the world - and many fans still haven't caught on.
Chris Hemsworth is one of the most recognizable actors in the Marvel Cinematic Universe - and thus, the world - for his masterful portrayal of Thor, God of Thunder. Hemsworth has appeared as the Odinson in a number of films, including Thor: Ragnarok, a movie in which he secretly played a secondary role.
The character Hajo is a three-headed gladiator from Sakaar who accompanies Korg and Loki to Asgard, where he falls in battle against Hela's forces. A different actor plays each of his heads via motion capture - Hemsworth plays the one on Hajo's right.
Taika Waititi received high praise for his work as the director of Thor: Ragnarok, and he also pulled double duty as an actor on the film - or, more accurately, quadruple duty. Waititi provided the voice and motion capture for the revolutionary Korg, and his face appears as one of the three heads of gladiator Hajo, along with Chris Hemsworth and stuntman Shane Rangi.
And Waititi's work didn't stop there, as he also donned a motion capture suit to record movement for both Hulk and Surtur.
Laura Haddock is easily recognizable for her performance as Star-Lord's mother, Meredith Quill, in both Guardians of the Galaxy and its sequel, but she appeared in the Marvel Cinematic Universe even earlier than that. Way back in 2011, Haddock had a brief cameo in Captain America: The First Avenger as a nameless autograph seeker who is visibly enthused to get up-close-and-personal with Steve Rogers.
It's understandable that some fans like to imagine this character as Peter Quill's grandmother.
Benedict Cumberbatch has taken the Marvel Cinematic Universe by storm with his depiction of Stephen Strange, the Sorcerer Supreme - one of many breakout characters from the franchise's third phase. Cumberbatch made appearances as Strange in Thor: Ragnarok and Avengers: Infinity War, but in his debut film, Doctor Strange, he played an additional role.
The actor stepped in to provide the voice for Dormammu - which means Doctor Strange is bargaining with himself in the film's memorable climax. According to Cumberbatch, this was done to create a clear parallel between Dormammu and Strange: "It's not immediately noticeable, but a lot of the animation is sort of like a mirror reflection, a rippled mirror reflection, of him, of Strange."