Sigourney Weaver Reunites With James Cameron For 'Avatar'

'There is something special about her returning to the genre in our film,' director says of 'Aliens' star.

When intergalactic baddies have you down, there's really only one person to call. Twenty-one years after Ellen Ripley scored one for the human race, "Aliens" star Sigourney Weaver is returning to space, reuniting with director James Cameron for a supporting role in his long-awaited film "Avatar."

"Sigourney and I have always looked back fondly on our collaboration in 'Aliens,' and we're excited at the prospect of working together again," Cameron said in a statement released to MTV News. "She has a special significance for fans of science fiction, so in addition to being perfect in all ways for the part, there is something special about her returning to the genre in our film."

The director's first movie since "Titanic" (see "Return Of The 'King': James Cameron To Spend Two Years With Aliens") centers on Jake Sully (Sam Worthington), a disabled war veteran brought to the exotic planet of Pandora to exploit its rich natural resources. Jake eventually switches sides, choosing to lead the indigenous people (the Na'vi) against mankind for control of the planet.

Potentially complicating matters for Cameron's intrepid hero is speculation that the Na'vi will be able to manifest themselves in a variety of physical forms, or "avatars."

Weaver is set to play Grace, a "veteran interplanetary explorer" who serves as Jake's mentor. "[Sigourney] has a unique blend of strength, sensitivity and intelligence needed to play the character of Grace, and I was thrilled when she responded so strongly to the script," Cameron said. "I can't wait to see what she creates."

Also joining the cast are Joel David Moore ("Dodgeball: A True Underdog Story"); CCH Pounder ("The Shield"); Peter Mensah ("Hidalgo"); Laz Alonso ("Stomp the Yard"); and Wes Studi ("The New World"). They join previously announced Worthington and Zoe Saldana, an actress perhaps best known for her work on "Pirates of the Caribbean: The Curse of the Black Pearl."

Cameron will begin principal photography on "Avatar" in April 2007, with a target release date of summer 2009. It will be filmed and released in 3-D.

The long delay is due almost entirely to the ambitious special effects Cameron hopes will fully realize his fictional and fantastical alien creatures and environments. Cameron will utilize state-of-the-art performance-capture technology for a majority of his shots, as well as a "real-time" virtual camera system that will enable him to direct CG characters and environments the same way he would on a live-action set.

The science-fiction icon previously broke new technological ground with revolutionary effects on films such as "The Abyss," "Terminator 2: Judgment Day" and "Aliens," the sequel that garnered Weaver her first Academy Award nomination for Best Actress.

Check out everything we've got on "Avatar."

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