Here’s a tale of chest-puffing courage and one-dimensional heroism from Russia during the second world war: an old-fashioned patriotic epic with slo-mo action scenes, intestines spewed on the battlefield and a soppy sentimental romance. It is based on real events in 1941, when more than 3,000 young military cadets were sent to the frontline to defend Moscow. Their mission was to buy time, holding off the Germans for five or six days until reinforcements arrived. Only a third survived.

The cadets are still three months from graduating military school when the order comes to mobilise. These lads are future Red Army commanders, the brightest and the best. Two of them, best friends Lavrov (Artyom Gubin) and Shemyakin (Igor Yudin), are in love with the same girl, trainee doctor Masha (Lubov Konstantinova). Good-looking Lavrov is a crack-shot gunner, recklessly brave and romantic. Shemyakin is gentle and decent, a bit dull. You can guess which one Masha kisses in the broom cupboard.

All three end up on the frontline, a town 200km from Moscow, as German tanks roll in. The soldiers around them are collection of cliches: there’s the strapping country boy dreaming of his mother’s borscht, and the speccy intellectual who translates when they capture a Nazi; otherwise, the Germans are a faceless horde.

“This is not a war, it’s a massacre,” says an army doctor as the bodies pile up. Hopelessly outnumbered, the cadets are shot, burned alive, blown to bits. But director Vadim Shmelyov actually seems a bit squeamish about immersing his audience in the hell, death and chaos of war. He seems more interested in glorifying the cadet’s sacrifice and valour with a clumsy jingoistic script. Take the lad blinded in battle, a bandage wrapped around his head. He’s refusing to go to hospital, professing to the heavens as the music swells: “I still have my hands. I can load machine gun belts.”

• Available from 8 March on digital platforms.