It's official - Marvel Studios says Chris Evans is now 100% confirmed to take the lead in The First Avenger: Captain America. And joining him in the action adventure will be Sebastian Stan as his sidekick, Bucky. Stan was in the running for the role of Captain America, but ultimately lost out to Evans.

While Evans and Stan are definitely onboard, Emily Blunt will not be joining the cast despite being offered a role. Blunt has passed on the opportunity to play the main character's girlfriend, according to a report in the LA Times.

Joe Johnston (The Wolfman) is directing from a script by Christopher Markus and Stephen McFeely. Marvel Studios' Kevin Feige is producing with Alan Fine, Stan Lee, David Maisel, Stratton Leopold and Louis D'Esposito executive producing. Paramount Pictures is aiming for a July 22, 2011 release.

According to Marvel, this first of what looks to be many films involving Captain America will concentrate on the early days of Steve Rogers and his beginnings as Captain America.

Evans (best known for playing The Human Torch in the Fantastic Four films), will next be seen in The Losers. He also has Scott Pilgrim vs the World and Puncture set for release later this year.