When you sign up to play a huge comic book super hero such as Iron Man or The Hulk you carry that image throughout however many movies a studio may need you for. You could be attempting to smash buildings into your late 50's!
When you sign on to be Captain America you're pretty set to have movie after movie under your belt. And Chris Evans' is at the point where he gets to pick; he wants to be in Thor: The Dark World. Evans has already agreed to portray America through 6 films, having two under his belt (Captain America: The First Avenger, The Avengers) with two more coming up (Captain American: The Winter Soldier, The Avengers 2), leaves two spots open. What's a hunky hero to do?
According to Collider, Mr Red White and Blue wants to make a cameo in the sequel to hammer wielding (super sexy) god Thor: "It's obviously going to be tricky trying to work out the plot, the reason why I am not there to help him, and why he is not there to help me...I would love to do a cameo...".
I hope it's a fight scene because that was hilarious to watch.