Josh Brolin Voicing Thanos in 'Guardians of the Galaxy'

<p>Josh Brolin (CAA, Ziffren Brittenham) will narrate &quot;Untamed Americas,&quot; a four-hour miniseries that explores wildlife spectacles in North, Central and South America, for National Geographic.</p>
The character first appeared at the end of "The Avengers."

Josh Brolin is voicing the character Thanos in Guardians of the Galaxy, sources tell THR.

The villainous character first appeared at the end of Marvel and Disney's The Avengers.

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Guardians, set for release on Aug. 1, stars Chris Pratt as Peter Quill, the leader of the misfit Guardians. Zoe Saldana, Dave Bautista, Vin Diesel, Bradley Cooper and Lee Pace also star in the film. The film is directed by James Gunn from a screenplay by Gunn and Nicole Perlman.

Thanos is a purple-hued alien who was born on Saturn's moon Titan. He's considered one of the baddest Marvel villains of all time, and is part of a group of god-like beings called The Eternals. He also trained Gamora (Saldana) to be an assassin. At the end of The Avengers, the character was played by Damon Poitier.

Brolin most recently starred in Labor Day and Oldboy. His upcoming films include Everest, Inherent Vice and Sin City: A Dame to Kill For, and he has just joined Denis Villenueve's Sicario. He's repped by CAA.

As usual with its projects, Marvel had no comment.

Latino Review first reported Brolin's casting.