Voguish director Damien Chazelle's pick for "the greatest movie ever made" isn't his masterwork La La Land, or even Citizen Kane. It's The Umbrellas of Cherbourg. Chazelle claims to have watched this New Wave classic more than 200 times, and regards his own not-quite-Oscar-winning 2016 musical as a crypto-remake of Jacques Demy's entirely sung-through phenomenon.

It wasn't love at first sight. Initially, Demy's film, with its strange operatic style, "threw me for a loop," says Chazelle. On its debut in 1964, it provoked a similarly perplexed response. Yet it went on to win the Palme d'Or and five Oscar nominations; it pulled in more than a million filmgoers in France alone, and became an enduring obsession for those, like Chazelle, who have fallen under its spell.

Such has been the film's hold that its fading celluloid has been subjected to a painstaking digital restoration. Realising that his Eastman stock would eventually degrade, Demy made three colour separation masters from the original negative. Their survival has enabled his original hues to be precisely recreated. His mono sound mix has been deepened with the help of the original album of the film's music.

At first sight, it seems to channel the gaiety of Vincente Minnelli's classic MGM musicals. The drab, war-scarred Channel port of Cherbourg is drenched in saturated primary colours. Interiors feature enchanting pastel, candy-striped rooms set off by the simple but exquisite clothes and hairstyles of their humble occupants. Bustling and vigorous street scenes are intricately choreographed. Yet this turns out to be no escapist fairyland. The dazzling cinematography brings home the harsh reality of everyday life in a dull, postwar provincial town at least as starkly as the same era's kitchen-sink British films.

Michel Legrand's lyrical, sweeping score secured one of the film's Oscar nods, but it provides none of a traditional musical's dancing choruses or showcase numbers for the leads. Instead, recitative conveys everything from an inquiry about the price of an umbrella to a declaration of love through the same unremitting threnody, in a continuous paean to the delightfulness of human experience, whether that be happy, sad or merely humdrum. And it's this peculiar device that establishes the film's game plan.

The Umbrellas of Cherbourg is a life-enhancing tragedy.

Yet it's a tragedy devoid of the greed, courage, sacrifice, betrayal or violence whose glamour mitigates calamity in more grandiose narratives. It boasts neither heroes nor villains. Instead, it confronts quotidian woes that evoke less awe than their more exalted counterparts but affect us more frequently and ultimately more profoundly. Its minor-key topics are disappointment, compromise and loss. Delicately, it extracts their sting and unites them with the joys life also offers.

The film's unforgettable title sequence features a Google Earth-style overhead view of rain pouring on to the cobbles of Cherbourg. Beneath the deluge, burghers go about their affairs under the efficient protection of brightly coloured umbrellas. Into all lives rain must fall, but it can be deflected by art. That is the invaluable function that Demy's masterpiece performs.