Peter Jackson's new World War One film, comprised of re-mastered archival footage, will get its world premiere at the BFI London Film Festival.
The project has been newly-titled They Shall Not Grow Old and will air at the event in October - and simultaneously in cinemas across the UK - to mark World War One's centenary.
The Lord Of The Rings director, who has won three Oscars, created his latest film in 3D, re-mastering 100-year-old footage from the Imperial War Museum's vast archives using modern production techniques to present never-before-seen detail.
Sir Peter said: "I wanted to reach through the fog of time and pull these men into the modern world, so they can regain their humanity once more, rather than be seen only as Charlie Chaplin-type figures in the vintage archive film."
He used "computer power to erase the technical limitations" of the footage, to "see and hear the Great War as they experienced it".
The footage is accompanied by the voices of war veterans.
BFI London Film Festival artistic director Tricia Tuttle said 100 years after the war people knew a lot about the "horrific" impact of the conflict.
"Especially the brutal scale of the casualties which decimated a generation, but Peter's film offers new understanding of the human experience of life at the front.
"The work his team have done on the materials, adding colour and converting to 3D, is painstaking and beautiful. It makes these people from 100 years ago seem so alive and gives an uncanny sense the footage was shot recently."
The premiere will be shown on 16 October.