Gary Oldman is the go-to guy for screen villains, and now, it looks like Lucasfilm may have gone to him to cast the role of a much-anticipated villain in ''Star Wars: Episode III.'' Oldman's manager, Douglas Urbanski, confirmed to EW.com that Oldman is in talks to voice the role of General Grievous, leader of the Separatist clone armies who are fighting the Jedi-led troops of the galactic Republic in the upcoming movie. (Like Darth Vader, Grievous is a part-mechanical character who wears a prosthetic mask, making it possible for George Lucas to have already shot his scenes and to add the voice later.) Lucasfilm spokesperson Lynne Hale declined to comment on the possible casting, telling EW.com it was only a rumor ''at this point.'' But Urbanski said that Oldman would play the role ''if he can find the time,'' noting that the actor still has to finish filming ''Batman Begins'' (in which he plays Jim Gordon, Batman's friend on the Gotham City police force). Plus, he's due to film ''The Longest Yard'' opposite Adam Sandler later this year, which will see him playing a prison warden. Meanwhile, Lucas is in post-production on ''Episode III,'' which is scheduled for release next May.