Mark Ruffalo, the third/fourth/fifth actor (depending on how you count) to play the Hulk once said of the role, "I look at it as my generation's Hamlet." Ruffalo does not mean that when Bruce Banner gets angry he transforms into a giant green Shakespearean tragic hero, he means that the role gets passed around many great actors of the time, much like Hamlet, and many other Shakespearean roles, used to be.
With countless remakes, reboots, and re-castings in movies these days, the same roles, like Hulk and Hamlet, often get played by many different performers. No actor has a monopoly on a single role anymore. Even iconic performances, such as Anthony Hopkins as Hannibal Lecter or Heath Ledger as the Joker, have found themselves recast.
Sometimes, the actor to take over the role has performed opposite the first actor before in another film. Before seeing the two actors in the same role in two different projects, you can see them in the same project in different roles.
This list won't include actors who played the same role in the same movie, such as Kate Winslet and Gloria Stuart in Titanic.
Here are ten co-stars who shared roles in other projects.