When words fail: "Quo Vadis, Aida?"

The Sarajevo-born writer-director Jasmila Zbanic has marked the 25th anniversary of the siege of Srebenica, that defining moment in the Balkan conflict, with Quo Vadis, Aida?, a film about a woman in the very middle of the middle of it. A teacher in peacetime, the eponymous heroine (Jasna Đuričić) has been recruited locally to interpret for the UN in their negotiations between the two factions. It's a crucial role: she doesn't just get to sit in the room, she also plays an active part in attempting to secure and reshape the region's future, determining what requires translation and what's best left unrepeated in the interests of keeping the lines of communication open. Very quickly, we pick up the stress involved; it's hardly a surprise Aida is most often observed with a cigarette on the go. The grave pressure doesn't relent once negotiations break down and the shelling begins, displacing thousands from their homes. One of Aida's sons makes it inside the UN's compound, hastily converted into a shelter, before the barriers come down; but the other is shut out, along with his father Nihad (Izudin Bajrovic). The method Aida alights upon to restore family unity is inventive, opportunistic and perhaps a little underhand - in other words, exactly the kind of choice people make in life-or-death situations. How wise it is will be called into question, minute-by-minute, scene-by-scene, as this situation develops. History tells us the siege will end badly. (A closing caption tallies the death count: 8,372.) What's up in the air for the duration of Zbanic's film is what exactly the damage will look like.

It's a thriller, then, but not one of those fun ones that steer us towards a final righting of wrongs and an unambiguously happy and reassuring ending. No, this is one of those thrillers - horror-thrillers, perhaps - which fill you with uncertainty and nag away at your guts. As if the wider tension of the negotiations failing wasn't enough, Aida finds herself zigzagging between stonefaced factions of men in military garb, and set upon by the refugee contingent - which includes many of her friends and neighbours - who attribute to her a power she doesn't really have within the UN chain of command. At best, she's a hired hand; at worst - and everything here tends to lean in that direction - she's apt to be regarded by the warring factions as one of them, innately compromised and therefore just about as disposable as anybody else on site. The advantage the character presents as a heroine is that she has mobility and access. Unlike those friends and neighbours, left sitting in place for much of these 100 minutes, caught between a rock and a hard place before finally being marched along straight lines towards their historical destiny, Aida has workarounds, ways out - or at least she thinks she does. That's enough to keep the film moving, even if it's just around the grimly functional interiors of the overrun, increasingly embattled compound.

Zbanic stages her crowd scenes - boasting hundreds of extras, representing the thousands of lives at stake in Srebenica - with great assurance, and adds a subtly affecting coda that gestures towards what it must have been like to live on in a country that was no longer recognisable; that appeared to have moved on, with so much business left unfinished and so many questions left unanswered. Yet our eyes are continually drawn towards this one representative woman, treading water in the midst of deadly sociopolitical turbulence. Keeping a schoolmarm's wits about her, Aida sees what's coming down the line when one faction sends bread to feed the refugees and buses to round them up; from a soldier's casually loaded inquiry about her son, she senses some personal animus is being pursued here, and that it's likely to end in bloodshed. She's certainly more alert than her UN colleagues, depicted as either wet-liberal soft touches or wet-nosed kids, hopelessly out of their depth when confronted by the grizzled war machines who swagger into shot, chief among them Ratko Mladic (Boris Izakovic). But this was one of those occasions where to be ahead of the game provided no consolation: Đuričić gives off a harried, nervous energy that transmits all too easily to the viewer. This would not be a good film to put yourself in front of if your New Year's resolution was to give up smoking - but it's a powerful one in many other respects. Zbanic eventually answers the question framed by her own title with a rare moral clarity and force. Where were the Balkans headed circa 1995? Towards outrage, carnage, infamy; towards images that require no translation whatsoever.

Quo Vadis, Aida? is available to stream from today via Curzon Home Cinema.