Robert Downey Jr has dropped out of Cowboys and Aliens. The world mourns. But while the actor has left the project, consolation can be found in the steadfast position on its helmer, Jon Favreau. Yes, the dynamic duo who brought us Iron Man have parted, but Favreau's fun approach will hopefully continue in the adaptation of Scott Mitchell Rosenberg's crazy graphic novel.

Cowboys and Aliens sees gunslinger Zeke Jackson team up with his Apache enemies to fight off a gang of invading aliens and their plans of world domination. But with Downey Jr too tired (or busy) after heading up two franchises, the hunt is now on for a new star performer. I'm sure I'm not the only one thinking this, but there's a clear choice to be had here. A gun for hire in a wacky sci-fi flick? Nathan Fillion, your time has come. Expect a Facebook campaign within the next week.