Warner Bros. Pictures won a bidding war earlier this month, plunking down a reported $50 million for the right to distribute what may be the most expensive movie ever made: ''Terminator 3: The Rise of the Machines.'' With a leather-clad Ah-nuld returning to the battle-hardened franchise, analysts say the deal is a near-certain coup for Warners (two outside production companies are funding the majority of a budget that could reach $170 million).

But before ''T3'' rumbles into theaters on July 4, 2003, moviegoers who've memorized every Austrian- accented quip from the first two films will have to adjust to some changes. ''Terminator'' auteur James Cameron will be gone, as will be stars Linda Hamilton and Edward Furlong, leaving Shwarzenegger as the sole returning creative force. Jonathan Mostow (''U-571'') will direct from a script by John Brancato and Michael Ferris (''The Game'') -- and a female Terminator will be along for a ride. Here's what else to expect:

Sarah Connor: Terminated After starring as waitress-turned-warrior Sarah Connor in the first two movies, Linda Hamilton (once married to James Cameron) opted out of ''Terminator 3.'' ''I retired as a champ,'' she tells EW.com, explaining that the role reached its peak in the second movie. But she was less diplomatic in an October interview with the English newspaper The Independent. ''I read the script and it didn't take my character in any new direction,'' Hamilton said. ''It was like a no-win situation for me. The best I could hope for was that I wouldn't be compared too unfavourably with myself 10 years ago. Without Jim breathing the breath of life into the film? No thank you.'' Rather than attempt a ''Hannibal''-style actress transplant, ''T3'''s producers have sliced Sarah Connor out of the script. ''They may have said, 'If we can't get her, why bother,''' says Hamilton's manager, Bobbie Edrick. ''It's better to write the role out than try to replace her.''

John Connor: Replaced Edward Furlong made his movie debut in 1991's ''Terminator 2,'' playing Sarah Connor's son John, who's destined to lead humanity in future battles against machines that take over the world. But Furlong, who has reportedly struggled with substance abuse, will not appear in ''Terminator 3,'' despite earlier reports that he had signed on to the project. (his publicist didn't respond to requests for comment on his absence). A ''T3'' casting call distributed to agents (obtained by fan site Dark Horizons) says that producers are looking for an actor between the ages of 20 and 24 to play John Connor, who is supposed to have aged a decade since ''T2.'' John ''has been struggling with an uncertain future, not trusting that the nightmares that haunt him are over for good, '' says the casting information, which describes the role as ''extremely complex... requiring tremendous emotional range and intensity.'' Hayden Christensen, call your agent now.

Kate, Brewster, and Scott: Added The casting call lists three major new characters (Warner Bros. and ''T3'''s producers declined comment on the document, which is presumably subject to change). Kate, the movie's heroine, is a ''young professional with a medical background'' who ''can give both John Connor and the Terminator a run for their money.'' Brewster is a high-ranking military officer with a science background; the ''Terminator'' series' looming nuclear apocalypse is supposed to occur after the U.S. military's computer system develops a mind of its own, so we'll probably see Brewster dealing with that little problem. The third new guy is Scott, ''a successful young professional who has everything going for him.'' Until the Terminator blows his head off.

The Terminatrix: Watch out! Long-running rumors of a female Terminator are true: She will be ''sexy, beautiful, composed and lethal,'' according to the movie's casting call. And ''T3'''s producers say they're looking for a performer of ''any ethnicity or nationality,'' as long as she's in fighting shape and between the ages of 20 and 30 -- a category that could encompass anyone from Lucy Liu or Jessica Alba to ''Mission Impossible 2'''s Thandie Newton. The character will have powers that dwarf even those of ''Terminator 2: Judgement Day'''s morphing T-1000. ''She can disappear, she can mold into someone else, and she is sometimes just an energy,'' Schwarzenegger earlier told the New York Post.

Most other details of ''Terminator 3'' are as secret as anything gets in Hollywood. (To prevent leaks, each copy of the script has its owner's name marked on every page, according to one source familiar with the production.) It is known, however, that the movie will shoot in Vancouver and Los Angeles beginning in April. Pre-production has already started, including discussions of casting and special effects. George Lucas' firm, Industrial Light & Magic, which did Oscar-winning CGI work for ''T2,'' is in talks to return for the third movie, according to sources close to the project (an ILM spokesperson declined comment). And hey, did we mention that Arnold will be back?