Alfred Mendes was just 19 years of age when he enlisted to fight in what was supposed to be the war to end all wars. Unlike many he survived, and unlike many of those who made it home, he shared some of his life-changing experiences with his family, memories of futility and chaos, bravery and heroism, much of it unsung. Grandson Sam never forgot them and, as director and co-writer of 1917, has brought them to the big screen in explosive style.

It’s a simple story but told on the most epic of scales. Two lance corporals (George MacKay and Dean-Charles Chapman) are given what sounds like a suicide mission – to venture miles across No Man’s Land and behind enemy lines in search of a British battalion and prevent them from attacking the Germans. If they do, it will be certain death. But it’s told in a way that will have your heart leaping out of your chest Mask-style, as the danger and tension escalates and the prospect of delivering that message appears increasingly out of reach. It’s all down to the combined talents of Mendes and the legendary Roger Deakins and their “one take” approach, giving the film a compelling immediacy and urgency. Made up of a series of long takes, seamlessly meshed together, the impression is of the action taking place almost in real time, a true cinematic experience rather than a film to be just watched.

The two soldiers go through a living version of Dante’s Inferno, although this version of hell feels like it has more than seven layers. The deserted but booby trapped German trench, the crashing fighter plane, the final dash to the destination amid constant, heavy bombardment, the huge, skin-crawling rats …. It’s an insane mission, one that will reduce you to tears both during and afterwards, as you become immersed in the action. And it never fails to remind us of the essential character of war – that, regardless of the weapons or locations, it’s destructive, horrific, devastating and what it destroys can never be repaired or brought back.

Yet there are moments of peace and relief, when Deakins – at the top of his form – shows us how normality can still exist: apparently untouched rural scenes are almost cheek by jowl with the hellish scenes of conflict and suffering. Somehow life goes on, despite extraordinary circumstances. Overall, he treats us to a brilliant visual feast, from the colours of those fields to the stark white chalk trench full of soldiers waiting to go over the top, with the camera simply following the characters and the action and taking the audience with it. Like the story, it’s simplicity itself and totally suberb.

Held together by the two central performances by MacKay and Chapman, it’s also peppered with cameos from such familiar faces as Andrew Scott, Colin Firth, Benedict Cumberbatch, Richard Madden and Mark Strong, yet their presence doesn’t jar. MacKay is especially impressive as a soldier so disillusioned by war that he swapped his medal for a bottle of wine but still repeatedly puts his life on the line to complete the mission and save hundreds of lives. This could be the role that catapults him into another league.

1917 was made for the cinema and that’s how it should be seen – on the biggest screen possible. Hold on to your seats and your tissues, because this is one of the great cinematic experiences of the year – and perhaps the decade.

1917 is on general release now.