Patrick Stewart officially becomes the second longest-serving Marvel actor after his confirmed role in Avengers: Doomsday, beating out Hugh Jackman, but there is one other actor still in first place. While the Marvel Cinematic Universe (MCU) has only been in operation since 2008, Marvel movies have been appearing on the big screen for much longer. With franchises like Fox’s X-Men, Sony’s Spider-Man, and Universal’s Hulk, there were plenty of other Marvel movies getting theatrical releases throughout the 2000s.