Sigourney Weaver and Stephen Lang have signed on for "Avatar 2", according to Movie Pilot. Avatar 2 is the sequel to the 2009 box-office hit and sci-fi epic, "Avatar". This latest casting confirmation has prompted fans and viewers of the film to question how Weaver's and Lang's characters are going to be written into the sequel, since they both died in the first film.

In Avatar, Weaver stars as xenobotanist Dr. Grace Augustine, who heads the Avatar Program. Lang is the main villain, Col. Miles Quatrich, who's the security head of Hell's Gate in Pandora.

The last time Grace is seen in Avatar, she is shot by Col. Quatrich. Jake Sully brings her body to Neytiri and Mo'at before the Tree of Souls, where the Na'vi unite in an attempt to save her life by transferring her consciousness into her avatar body. Grace succumbs to her wounds and dies before the process can be completed. Col. Quatrich, on the other hand, suffered a more brutal death. Neytiri shoots him twice through the chest with her father's bow.

IGN reported that in a press event for the Blu-ray release of the extended collector's edition of Avatar, Cameron talked about his plans for the sequels. In that same event, he questioned the certainty of Grace's death and stated teasingly that "nobody dies in a science fiction movie". He then implied that it's up to Weaver's agent whether Grace lives or dies in the sequel. His statements have led to some speculations on how her "death" would be explained away if she does reappear in the sequel. Whether or not Weaver reprises the role of Grace or comes back as a new character altogether remains to be seen.

Aside from Avatar 2, Lang has also signed on for "Avatar 3" and "Avatar 4". Cameron has commented that Lang's character was so memorable in the first film and that he's happy to be working with him again. He adds that the Col. Quatrich character would evolve throughout the three sequels.

Cameron will again be writing the screenplay and directing the film. He will also collaborate with other Hollywood screenplay writers for the Avatar sequels. According to MNR Daily, on board for screenplay writing duties are Josh Friedman ("War of the Worlds"), Amanda Silver and Rick Jaffa ("Rise of the Planet of the Apes"), and Shane Salermo ("Armageddon").

Zoe Saldana and Sam Worthington are confirmed to reprise their roles as Neytiri and Jake Sully. Avatar 2 will debut in theaters worldwide on December 25, 2017. Avatar 3 and Avatar 4 will open consecutively on December 25, 2018, and December 25, 2019.