[With Andre Ovredal's opening in limited release in the US tomorrow we re-visit our earlier review.]

Trolls. They're big. They're dumb. They eat rocks. And - as it turns out - they are not just a fairy tale creation.

Thomas, Kalle and Johanna are a trio of student film makers striking out to the remote parts of Norway on assignment. Their task: Find and question the illegal poacher roaming the region taking down bears - a closely regulated animal population - as he goes. With the help of local hunters they track the man down, a solitary soul named Hans who roams the countryside in his battered landrover and pungent trailer. But once they finally get Hans to talk what they find is not at all what they expect.

Because, you see, while Hans is indeed a hunter - and one who works resolutely off the books - bears are not his quarry. No, the bears are a cover up. Hans' real targets are trolls. Real trolls. Enormous brutes who roam the forests and mountains of the far north of Norway, their existence carefully covered up by a secret government agency. When the trolls break out of their assigned areas it is Hans' task to hunt them down, using his specialized weaponry - a giant UV flashlight, basically, which produces simulated sunlight strong enough to turn the beasts to stone or cause them to explode depending on the troll variety - to neutralize the threat.

It's a hard job. A brutal one, even. One that demands incredible hours, constant danger, and coating oneself with 'concentrated troll stench' every night, to avoid detection. And with an increase in troll activity forcing Hans out into the field night after night with no additional compensation he's just flat out sick of it. And so he welcomes the students along to blow the lid off of the whole thing.

Shot in a documentary style, Troll Hunter is a wry, straight faced creature comedy. While recognizing that the audience wants trolls - and delivering plenty of them - the heart of the piece is really the dry cynicism of Hans balanced against the naive optimism of student leader Thomas. Structured as a basic road movie - something has driven the troll population out of one mountain highland, wreaking havoc elsewhere and the group must discover what - director Andre Ovredal neatly balances tributes to classic fairy tales, with understated character work, some sly running gags - the riff on trolls being able to smell the blood of Christian men is a good one that pays off a few times - and hugely impressive special effects with the trolls themselves.

As for the actual trolls, there are plenty. Designs are based directly on the early Norwegian folk tales - so much so that those familiar with the classics should find the beasts immediately familiar - and the creature animation and integration with the live action footage - all of it done in house - is pretty much flawless.

Troll Hunter makes for an interesting counterpoint to similarly styles Hollywood films like Cloverfield. Where the US approach is to make everything bigger and more epic - the destruction is global and the creature unmissable - the charm of The Troll Hunter is that while the creatures are big the scope of the story remains small. These events are hidden, we're being given a glimpse of a secret world from the perspective of a small, contained group of people. A surprisingly intimate creature feature, Troll Hunter is great fun.