Three years before Richard Attenborough’s movie version of Oh! What a Lovely War there was this anti-war satire, set in 1918, now on rerelease – Philippe de Broca’s King of Hearts. Regarded by many, including its director, as a classic, it nonetheless flopped hard at the box office. Watching it again now, I find myself not quite able to hail it as a masterpiece, more of an engaging and contrived oddity – like a U-certificate Marat/Sade – exoticised by the spectacle of non-English-speaking actors dubbed in order to play Scottish soldiers.

Just before the end of the first world war, the German forces retreat from a French town (the young soldier Adolf Hitler has a brief, wacky cameo) but booby-trap it with a bomb timed to go off at midnight. The inhabitants flee in panic and the patients of a local mental hospital escape and have the run of the place. Then bewildered Scottish soldier Charles Plumpick (Alan Bates) is ordered in to defuse the bomb, chiefly because of his ability to speak French, and he is acclaimed by the escaped patients as their King of Hearts.

It is a kind of Rabelaisian story, a carnival of misrule and anti-rule, with the humblest exalted, the arrogant cast down and everything a whirl of craziness – that craziness being of course the only sane way to respond to the insanity of war.

There is an element of boisterous whimsy in this film, and colourful gaiety: a young and breathtakingly beautiful Geneviève Bujold makes an early appearance as a young sex worker who falls in love with Plumpick. But it has dated a little and you might need a sweet tooth for the sentimentality. It is orchestrated by De Broca with tremendous elan.