Despite some of the marketing, Chris Crow's zeitgeisty paranoia thriller owes as much if not more to Hitchcock's Lifeboat as it does to modern "torture porn", such as the Saw sequels. This is a slow-burning, character-based ensemble piece, tightly written and unfussily directed, which takes our web-based fears and makes them monstrously manifest; not only our anxiety about identity theft, but also touching upon our perceived anonymity, leading as it does to a sense of invulnerability - and from behind that veil, the screenwriters suggest, we are free to act upon our cruellest base desires with virtual immunity.
Inevitably, perhaps, the tension gives way to more visceral final act, but Crow's camera never lingers or leers. The 18 certificate (in the UK) seems harsh, given the recent, similarly-budgeted excesses of Tom Six and Srðan Spasojeviæ, from which this is a mercifully far cry.
One may well be left with the feeling that this is a desperately topical film, cashing in on the current trends for horror games and social networking - and this is not an unreasonable response. But there is real quality here, not least in the four central performances, superbly depicting the rapid mental decline as the dire situation dawns: that they've been given the trip of a lifetime, and it looks like it'll be the last of their lives. This descent could have been unconvincing, but as the laughter fades and the camera becomes unfixed, the effect is quite involving.
It's a pity that this kind of ingenious lo-fi horror is so often lost in the shadow of dismal Hollywood remakes. We can help right this wrong by supporting freshness and ingenuity where we see it.