Downey Jr. Out of ‘Cowboys & Aliens’; Favreau Still Directing

Robert Downey, Jr. has fallen out of the Jon Favreau-directed sci-fi western Cowboys & Aliens, The Los Angeles Times reports. The movie, according to LAT sources, will still move forward with Favreau, however.

DreamWorks is said to be seeking a new hero to replace Downey with production tentatively set to begin this year for a planned release in summer 2011.

Cowboys & Aliens focuses on outer-space creatures who land in Arizona circa mid-19th century intent on enslaving the local population — until a group of cowboys and Apache Indians fight back.

Downey was set to play the gunslinger Zeke Jackson for his Iron Man director, but scheduling issues forced a re-think, says the LAT. His parting with Cowboys could re-ignite speculation that a Sherlock Holmes sequel is on the fast track…