Production for Avatar 2, the sequel to the hugely successful and highest grossing film of all time Avartar, was supposed to have begun in 2014 for its original scheduled release in 2016. But a number of factors, including a very ambitious plan by James Cameron as well as the untimely death of music composer James Horner have pushed back its release to Christmas 2017.

As Cameron becomes more successful in the box-office, he is given more leeway to pursue his creativity. For Avatar 2, iMDB reported that the famed director wants to shoot many of its scenes underwater. To enable him to film motion-capture performance underwater, Cameron is said to be developing a new technology - and a new submarine - to allow him to pursue this dream. He also plans to shoot all three Avatar sequels back-to-back-to-back.

Despite the delay, pre-production is currently underway and Fox chairman and CEO Jim Gianopulos is very patient with pace the pro-production is on-going. He told Variety, "Cameron has his own pace."

It was also reported that the untimely death of Horner, who collaborated with Cameron in his other blockbuster hits like Titanic and Aliens series, may have affected Cameron and caused delay in the filming of Avatar 2, reported Franchise Herald.

Cameron and his Avatar producing partner Jon Landau issued a joint statement honoring Horner and said "the Avatar community has lost one of our great creative lights."

The joint statement further reads, "James' music was the air under the banshees' wings, the ancient song of the forest, and the heartbeat of Eywa. We have lost not only a great team-mate and collaborator, but a good friend. James's music affected the heart because his heart was so big, it infused every cue with deep emotional resonance, whether soaring in majesty through the floating mountains, or crying for the loss of nature's innocence under bulldozer treads.

"The beauty and power of Avatar lay not just in the superb performances and the visual splendour, but in the music that made us cry and exult along with our characters. Irayo, James. Fly brother.''

It was also rumored that the 60-year-old Cameron is having some difficulty adjusting the script of the series for a trilogy because it was originally written for four sequels.

In late April, it was reported that Cameron does not want to do a fifth installment of Avatar and instead wanted to make only a trilogy sequel.

"There's a layer of complexity in getting the story to work as a saga across three films that you don't get when you're making a stand-alone film," James Cameron was quoted as saying.

Before his death, Horner also confirmed Cameron does not want a fifth Avatar and was having problem keeping the franchise manageable, according to the IBTimes.

"Right now Jim [James Cameron] has four sequels, script wise," Horner said then, "And he's trying to make it into three. And that is where, I think, his effort is going right now. To keep it to three sequels. Because he's got so much going on how do you keep it from expanding into a fifth movie, total. And he'll get that sorted out."