After 2009's Avatar made more money than some entire countries have in their back account, a sequel was all but inevitable. However, as director James Cameron has proven in the past, he likes to do things larger than life. And according to Showbiz 411, he's gearing up to shoot Avatar 2, Avatar 3, and Avatar 4 all at the same time. The site goes on to report:
When Political Animals finishes shooting, see if you can follow Weaver’s schedule: she goes right into a new Christopher Durang play for a short run at Lincoln Center. Then she films Avatar 2, 3, and 4 with James Cameron. That’s right: they’re making three sequels to the blue 3D phenom all at the same time. Weaver says she has no idea how long it will take, or how it’s going to work. “I just show up,” she said. If Political Animals is renewed, USA will have to wait until all that’s over. And it’s not like Weaver is the only busy person in her household: husband director Jim Simpson is debuting a new play by A. R. Gurney at the Flea Theater this fall.
If this winds up being true, it will be a monumental filmmaking task in the same vein as the Lord of the Ringstrilogy; only much bluer. We'll be sure to have more information on this when/if it gets confirmed by either the studio or Cameron himself.