Bouncing into cinemas over sixty years after it was first released, The Dam Busters was back on the big screen. And what better occasion than the 75th anniversary of the actual dam raids themselves. Beamed from a special event at the Royal Albert Hall and screened across the country for one night only, The Dam Busters flew again. To the sound of Eric Coates’ iconic ‘Dam Busters March’ known to generations, many of whom have probably never even seen the film, history came alive. And aptly so, as the last surviving British dam buster Johnny Johnson, in his 90s, prepared to take to the skies once more in a Lancaster. In his video message to the Albert Hall, Johnson acknowledged he was now representing the 133 lads who took off on the raid to breach the great dams of Germany, to flood the industrial heartland of the Reich and to hit Hitler on his home ground. A morale booster at the time, the raid was immortalised in Paul Brickhill’s book The Dam Busters, and in Wing Commander Guy Gibson’s Enemy Coast Ahead. And as the lights dimmed, we experienced again why The Dam Busters - the movie - has moved the British people ever since, seeming to summarise its spirit and courage.

In 1943, the war was not going well for Britain. German forces had swept across Europe and seemed unstoppable. Scientist Barnes Wallis hatched a scheme to breach the Mohne, Eder and Sorpe dams in the Ruhr valley. To the RAF high command it seemed crazy. Bouncing bombs, designed to skip over enemy defences, delivered by specially adapted Lancaster bombers, to be flown at the insanely low level of 60 feet while flak and anti-aircraft guns blazed around. But Guy Gibson, the no-nonsense and exceedingly experienced pilot – at still only 24 years old – saw the possibility, and the originality, of the idea and agreed to lead the raid.

Often hailed as the best British war movie – it’s much more than that. It’s about character. The crack-pot wizardry, and indefatigability, of Barnes Wallis (played by Michael Redgrave); the leadership and calculated bravado of Guy Gibson (Richard Todd); and the bravery of the boys, hardly more than that, who volunteered to serve. And it’s about the character Britain in 1943, if not of 1955 when the film premiered 12 years to the day since the raid itself. Filmed by the late director Michael Anderson in - by then - unfashionable black and white, it suited his documentary, understated style. And that’s what you notice most – the understated, let’s-get-on-with-it, low-key heroism. Surprisingly perhaps, it’s also what the original reviewers noticed and applauded the most. Not so the Americans whose story this wasn’t – and who cut the slow-burn camera-tracking that happens before and, devastatingly, after the raid, quietly moving through the boys’ refectory and bunk rooms, noting without comment those no longer there.

A ‘war film’ doesn’t do The Dam Busters justice. For the first half, it’s about Barnes Wallis and the tense, scientific and political battle to get the bouncing bombs green-lit. The second half is about Gibson’s preparation for the raid and the nail-biting operation – Operation Chastise - itself. There's a tad too much of the bumbling boffin about Redgrave’s Barnes Wallis – which Wallis' daughter, at the Albert Hall event, roundly criticised. But Richard Todd, a somewhat forgotten 50s star, is convincing as Gibson – nailing the boyish demeanour and steely brilliance of the soon-to-be decorated commanding officer. Sure, the special effects, even at the time, were not the best, particularly for the water explosions. But the build-up and the focusing of the tension on Gibson – mainly through his eyes and voice – is cinematic gold. And not for nothing did George Lucas hail The Dam Busters as the key influence in how he staged the climax of Star Wars, Luke Skywalker’s x-wing fighter dealing death to the Death Star.

No women are present, apart from Barnes Wallis’ wife. It was noticed at the time. The Americans baulked at the lack of a love story. Ah, but the devastation the raid caused: a modern quibble that some critics also noted in 1955. But it’s not about that. It’s a quiet, undemonstrative – and thereby highly affecting – commemoration of what the 133 airmen gave and achieved.

Funny, plainly-poignant, timeless and yet very much of its time, The Dam Busters is a quietly rousing film. Carefully crafted, its heart and humanity are so well-woven their subtleties steal over you. And while everyone knows the theme tune – arms out, pretending to be a plane - its fully-orchestrated use only last 45 seconds, as lorries take the lads to the planes: half a minute of sublimely prosaic emotion. One can only wonder what Stephen Fry and Peter Jackson’s much-touted, unproduced remake would look like. The special effects may be better. But Michael Anderson’s movie has stood the test of time. And as a commemoration, and as a time-capsule of film-making you just don’t see anymore, The Dam Busters simply soars.