Director James Cameron is leaving no stone unturned in making sure his Avatar sequels match up to the high standards set by the first movie. The director has been hard at work developing the scripts for three Avatar sequels with screenwriters Josh Friedman, Rick Jaffa, Amanda Silver and Shane Salerno. All three scripts were expected to be completed in the first half of 2015, but in a recent interview Cameron stated that they still need polishing.

"I'm in the process of doing another pass through all three scripts right now," Cameron told Entertainment Weekly. "Just refining. That's in parallel with the design process. The design process is very mature at this point. We've been designing for about a year and a half. All the characters, settings and creatures are all pretty much [set]."

Talking about living up to the ridiculously high box office and audience expectations from the sequels, Cameron said, "Obviously, expectations are going to be very high on these films, especially on Avatar 2, to make sure it wasn't just some big fluke the first time," Cameron admitted. "So we've got to deliver. I've created a nice rod for my own back, so they say."

Back in June, a report from Variety had revealed just how much work Cameron has to do in order to complete Avatar 2. "It's a room ... which is covered floor to ceiling with images, characters, worlds, settings," said 20th Century Fox chairman and CEO Jim Gianopulos. "It's the most amazing, breathtaking thing you've ever seen. His challenge is to put all of that in a movie."

Avatar 2 is expected to release in December 2017.