'1917' interview: Sam Mendes explains how invisible CGI helped achieve his 'one take' vision

Whichever way you look at Sam Mendes’ new film 1917, it’s an astonishing filmmaking achievement.

Taking place at a pivotal moment during the Great War, it sees two British soldiers (George MacKay and Dean-Charles Chapman) tasked with delivering a crucial message to the front line in order to save thousands of allied lives.

The impeccable production design, costumes, and cinematography (from Oscar-winner Roger Deakins) completely immerse you in the desperation and omnipresent mud of trench warfare. The gripping script from Mendes and Krysty Wilson-Cairns, while propelling the story forward at an astonishing rate, never loses sight of the impact of war, the epic scope of the conflict, or the human sacrifices at its heart.

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The acting from the two leads, and its star-studded supporting cast (Colin Firth, Andrew Scott, Benedict Cumberbatch, Mark Strong, Richard Madden) is all first rate stuff that plays out amidst incredibly realistic and nerve-jangling pyrotechnics, but did we also mention that the film plays out across two very long single takes in real time, in the vein of the Oscar-winning Birdman?

Sam Mendes says he deployed every trick in the book (including the classic walking in front of the camera) to break up the long takes, the longest of which was around nine minutes long.

“Most of the time, a different kind of sleight of hand [was used to break up takes], things that you simply wouldn’t expect,” Mendes shares with Yahoo.

“Sometimes it’s at the greatest height of the action [that it’s done]. It’s all about how you direct the eye. But I hope people aren’t scrutinising it to work it out. They’re welcome to the second or third time they see it, but the first time, the camera and the journey of the camera, and the way that it operates, is not something that I want the audience to really think about. I want them to think about the story.”

Six months of rehearsals were crucial to the success of the film, not just for the actors, but for the camera operators, set designers, and pretty much everyone involved in the production.

“The whole thing is like a choreographed dance really,” explains Dean-Charles Chapman, “with the cameras and the actors and the set. The set was built around our performance.”

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Despite the best efforts of the filmmakers though, they simply weren’t able to complete the film without a certain amount of digital trickery from London-based VFX supremos MPC, as the director explains.

“There’s a lot of very subtle visual effects throughout. Not just in service of the ‘one shot’, but also in environmental art, locations, set extensions, that sort of thing, but very, very beautifully done.”

“Sometimes, the most difficult thing with visual effects is to make them photoreal, and make them not look like visual effects.

Sam Mendes’ 1917 arrives on 10 January 10, 2020. Watch a behind-the-scenes featurette below.