Brad Pitt has had discussions with the producers of Sherlock Holmes to star in a sequel as the detective's nemesis Moriarty, according to people familiar with the project.

No deal is in place for Pitt, currently in theaters with Inglourious Basterds, and there's still three months to go until the first picture is released on Christmas Day.

Robert Downey, Jr. plays Holmes in the Warner Bros. project, which Guy Ritchie directed. Jude Law plays Watson, and Rachel McAdams stars as love interest Irene Adler. Much of the talent is expected to return in the new picture, as could Ritchie as director.

Pitt has been the subject of a litany of blog rumors as appearing in several shots of Holmes as Moriarty, but those familiar with the script say the character is in shadow and cannot be recognized.

It's increasingly common for a studio to begin developing sequels ahead of a movie's release, enabling a second picture to get into production faster than it normally would, and at a comparatively low cost. Warners began pushing The Hangover, as the movie's prerelease buzz began to grow, though did not close deals until after the movie had begun raking in box office dollars.

Warners is keen on developing new franchises, with Holmes -- with its broad fan base and rich source material -- considered a very appealing candidate. The project would also mean Downey would star in a second franchise, after Iron Man, while DreamWorks could build yet another franchise around him with Cowboys and Aliens.