Up on the surface, meanwhile, the Nicholas Monsarrat-penned tale The Cruel Sea (1953) has also aged well, with Jack Hawkins, Donald Sinden, Stanley Baker and a young Denholm Elliott manning a rust bucket corvette against the U-boat menace. Allied convoys are a tougher nut to crack and, as the film depicts, escorting destroyers and corvettes are a terrifying threat to Jürgen Prochnow and his crew.

But the so-called ‘Happy Time’ of easy kills is over. At this point, America is yet to join the war and the bright lights of the East Coast helpfully silhouette Allied shipping for the U-boats lingering in the shallows. It’s October 1941 when U-96 slips berth in La Rochelle, stocked full of provisions like a Nazi-run branch of Whole Foods, and heads into Atlantic convoy lanes. It’s also a damn fine piece of history, based as it is on U-boat veteran Lothar-Günther Buchheim’s wartime experiences and with two other veterans (including submarine ace Heinrich Lehmann-Willenbrock) acting as consultants during the shoot. Wolfgang Petersen’s Das Boot (1981) ( above) is, of course, one of the finest men-in-peril movies this side of Predator. The Wehrmacht’s post-Stalingrad retreat and slow disintegration, meanwhile, is best captured (and often in slow-mo) by Sam Peckinpah’s Cross Of Iron (1977). As a bonus, there’s no romantic subplot involving Jude Law. Needless to say, it’s not exactly jolly viewing – one T-34 assault is teeth-grindingly fierce – but it offers a realistic vision of the battle’s hand-to-hand, factory-by-factory clashes, and its traumatic impact on the combatants. There’s been a Hollywood version of the battle ( Enemy At The Gates) and a recent Russian one (in 3D!) but only the German take, Stalingrad (1993) ( above), is worth searching out. The German army went into the key battle – Stalingrad – with 300,000 men and 500 tanks, emerging six months later with about five men and a small van. Aside from a few summery days in 1941, it was Russia that was doing most of the winning – although amid the slaughter it was often pretty hard to tell. Military historians will tell you that the “Ostfront” was where World War II was won and lost, and no-one who wears tweed for a living makes this kind of stuff up.

Ww2 movies tank battles