Watch Wendy Ide's video report on Waltz With Bashir

Last year’s hints of an Israeli cinema renaissance are given further weight by this unsettling examination of the brutally surreal nature of modern combat. Ari Folman’s potent, deeply personal antiwar film, which has been screened in competition at the Cannes Film Festival, is flagged up as the first feature-length animated documentary. In fact, it shares some common ground with last year’s Cannes competition title Persepolis – an eye-catchingly graphic animation style, a Middle Eastern setting, a backdrop of political unrest. But while the latter is a richly detailed memoir of a childhood in 1970s Iran, Waltz With Bashir deals with Folman’s almost complete lack of memories of a period in his late teens which is revealed to be so traumatic that he has inadvertently blocked out the details.

We are invited on a voyage of discovery into Folman’s uncharted subconscious after his late-night mercy dash to a friend plagued by nightmares of being pursued by slathering hounds. It’s a strikingly animated opening sequence, with a colour palette of brooding slate blues and angry ambers highlighting accusing eyes and teeth. The dreams, concludes Folman’s friend, are connected to a time in the early 1980s when both men were teenaged soldiers during an Israeli Army mission in the first Lebanon war. It is at this point that Folman realises that, although he knows he was present during the massacre of Palestinian refugees by a Christian Phalangist militia in August 1982, he has little concrete recollection of the events.

Folman then sets about gathering testimonials from friends and former colleagues to try and colour in the virtually blank sheet of his memory. The voices of seven of the nine interviewees appear in the film; for personal reasons the other two preferred that their words were spoken by actors. The interviewees and their fragmented recollections of the war are animated – the beauty of this approach is that while audiences may have become inured to the power of news footage and descriptions of atrocities, Folman’s eerie animated images have a way of jarring us out of our comfort zone.

A traumatised boy soldier is reflected in the eye of a dying horse; naked, numb recruits wade out of a sea dyed gold by illumination flares; a child’s hand and tousled head is partially obscured by the rubble of her family home. The emotional dislocation and the unreal quality of war is written in every frame.

The animation style is effective but somewhat unsophisticated. There’s a lack of fluidity to the movements. Characters’ gestures are stiff and slow, as if they slept awkwardly and their limbs have gone to sleep or they are still locked in a waking dream – which, in effect, they are.

Folman’s recovered memories do not sit easily on his conscience. As a witness of and indirect participant in the genocide of a group of people interned in a camp, he finds an uncomfortable parallel with the Holocaust. But the film’s most damning moment is reserved for the then Israeli Minister of Defence, one Ariel Sharon. An interviewee recalls that when he informed the minister in a late-night phone call that a massacre was suspected, Sharon said “Thank you for bringing it to my attention” and promptly went back to sleep.

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