Yahoo! Movies have unveiled the first official teaser poster for Cowboys & Aliens.

Directed by Jon Favreau (Iron Man), Cowboys & Aliens stars Daniel Craig, Olivia Wilde, Paul Dano, Harrison Ford, Sam Rockwell, Noah Ringer and Adam Beach.

Cowboys & Aliens, based on the graphic novel of the same name, will be released on July 29, 2011 by Dreamworks.

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 (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.

Check out the teaser poster below: