It's no secret the Avatar films are a gigantic technical feat - pushing the boundaries of cinematography, animation and performance capture.
But you may not be aware that the same applies to the music.
Composer Simon Franglen says work on the third instalment, Avatar: Fire and Ash, took an epic seven years to complete.
Along the way, he wrote 1,907 pages of orchestral score; and even invented new instruments for the residents of the alien planet Pandora to play.
And, with director James Cameron tinkering with the edit until the very last minute, the British musician only finished his final musical cue five days before the film was printed and delivered.
