It's ba-a-a-ck ... and longer than ever.

James Cameron's sci-fi epic "Avatar" revisits global multiplexes this weekend in a quest to pad its record $2.74 billion worldwide box office and hype DVD and Blu-ray Disc special editions planned for the fall. In fact, the theatrical rerelease is billed as a "special edition" of the eco-themed fantasy based on an extra 8-1/2 minutes of footage featuring additional action segments and other scenes.

The 2D DVD and Blu-ray Disc special editions expected to hit store shelves in November will feature at least 16 minutes of extra "Avatar" footage, a source told The Hollywood Reporter. A 3D version of the movie won't be available for home entertainment until next year.

"Avatar" producer Jon Landau said in an interview that new scenes included in the now 171-minute theatrical special edition involve action sequences and narrative-deepening extensions of key scenes involving the blue-skinned Na'vi of Pandora and their human visitors.

"We tried to look at what people have responded to in the film and give them more of that," Landau said. "There's a whole new scene that takes place in the (Na'vi) school, there's more night bioluminescence, there's new creatures, and there is a new action scene. The scenes don't just feel like added scenes -- they are very organic to the story and embellish it."

"Avatar" originally bowed in 2D and 3D on December 18, but the theatrical special edition will be shown only in 3D venues.

"About every 15 minutes you'll get something new that you haven't seen before, which is kind of cool," Fox domestic distribution chief Bruce Snyder said. "People want to go back to Pandora on the big screen."

Starting Friday, Fox will distribute the stretched "Avatar" in more than 800 U.S. and Canadian theaters, including roughly 125 Imax venues, though most of the latter specialty auditoriums will play "Avatar" for two weeks only. Cameron shot several "Avatar" scenes using Imax cameras, and the global blockbuster stands as the specialty exhibitor's top-grossing title with $236 million worldwide.

To date, "Avatar" has rung up $749.8 million domestically and $1.99 billion in foreign coin. Prerelease projections have "Avatar" fetching somewhere in the mid- to high-single-digit millions this weekend, but execs are more uncertain about what to expect from the rerelease in total.

The version 2.0 "Avatar" also is being released on more than 1,000 locations in 14 foreign territories including the U.K., Russia and Taiwan this week, including 50 overseas Imax sites. The pic's theatrical special edition will bow later in some other countries, with Japan set to get the super-sized "Avatar" in October.

Fox Home Entertainment released a 2D version of the original 162-minute "Avatar" on DVD and Blu-ray on April 22. Neither version offered any special features, yet the DVD remains the top-grossing disc release of the year, and the Blu-ray version set a format sales high in just its first four days. Fox hasn't announced a specific date for 2D special editions of "Avatar," which will feature even more extra footage and several bonus features.

The picture's release in 3D Blu-ray is delayed until 2011, because Fox and Cameron's Lightstorm Entertainment want to allow time for the installed base of 3D capability home entertainment systems to grow. Similarly, Paramount Home Entertainment has yet to release Cameron's 1997 theatrical opener "Titanic" on Blu-ray, continuing to hold out for a bigger installed footprint of the high-def format. Plans now call for a 3D conversion of the disaster classic for a theatrical 3D rerelease in 2012, but Paramount remains mum regarding home-entertainment release plans for "Titanic."