Could Brad Pitt be joining Robert Downey Jr. in the sequel to Sherlock Holmes? An insider with knowledge of the production has suggested to CinemaSpy that is indeed the case.

That individual did not mention a role, but the listing for "Untitled Sherlock Holmes Sequel" at IMDB Pro has two actors listed: Robert Downey Jr. and Brad Pitt. Pitt's role: Sherlock Holmes' arch nemesis Professor Moriarty. The listing also shows Guy Ritchie as director of the project.

The sequel, which has not officially been green lit by Warner Bros., could be shooting by June, if the studio has its way. Warner Bros. reportedly commissioned a sequel script by Kieran and Michele Mulroney last fall in the event the franchise reboot was a success.  

Sherlock Holmes, which stars Downey as the sleuth and Jude Law as Doctor Watson, had the biggest Christmas Day opening on record, and the worldwide gross is approaching $300M.

Given the reception of the first film, it's not a stretch to suggest that filmmakers and Warner Bros. would want top notch and bankable talent for the sequel. And now that Downey has officially pulled out of Cowboys & Aliens because the shooting schedule conflicts with the proposed June start for the Holmes sequel, we're not going to surprised if this rumor becomes official soon.