The cast for Jon Favreau‘s upcoming film, Cowboys & Aliens was already impressive with the likes of Daniel Craig, Olivia Wilde, Harrison Ford and Sam Rockwell to name a few. Now comes word that Keith Carradine (Dexter, Dollhouse), Paul Dano (There Will Be Blood) and Clancy Brown (Lost, The Shawshank Redemption) have joined the cast.

Deadline reports that Dano and Brown are both set to play cowboys while Carradine is set to play the town sheriff. The film is currently expected to start shooting in 2D this June, but director Jon Favreau stated via twitter that they are testing 3D for the film.

Official Synopsis:

1873. Arizona Territory. A stranger (Craig) with no memory of his past stumbles into the hard desert town of Absolution. The only hint to his history is a mysterious shackle that encircles one wrist. What he discovers is that the people of Absolution don’t welcome strangers, and nobody makes a move on its streets unless ordered to do so by the iron-fisted Colonel Dolarhyde (Ford). It’s a town that lives in fear.

But Absolution is about to experience fear it can scarcely comprehend as the desolate city is attacked by marauders from the sky. Screaming down with breathtaking velocity and blinding lights to abduct the helpless one by one, these monsters challenge everything the residents have ever known.

Now, the stranger they rejected is their only hope for salvation. As this gunslinger slowly starts to remember who he is and where he’s been, he realizes he holds a secret that could give the town a fighting chance against the alien force. With the help of the elusive traveler Ella (Olivia Wilde), he pulls together a posse comprised of former opponents—townsfolk, Dolarhyde and his boys, outlaws and Apache warriors—all in danger of annihilation. United against a common enemy, they will prepare for an epic showdown for survival.

As a side note – in 2004 Keith Carradine played Wild Bill Hickock in the HBO series Deadwood and back in 1995 he played Buffalo Bill Cody in the movie Wild Bill, which starred Jeff Bridges as ‘Wild Bill’ Hickok – so, he’s no stranger to playing a Cowboy.

Cowboys & Aliens is slated to hit theaters on July 29th, 2011.