There are a fair number of precedents, but there's a case for suggesting that The Blair Witch Project and especially Open Water gave birth to a new sub-category of the horror genre, which for want of a better term I'll call the Minimalist Horror Film. In Minimalist Horror, what plot there is functions primarily to transport the lead character(s) to the location where they will be terrorised for the rest of the film, at the end of which they will either be killed or escape with their bodies and sanity in tatters. The formula is proving quite popular in Europe – just a few days ago I caught Fabrice Du Welz's The Ordeal [Calvaire], in which poor old Laurent Lucas breaks down close to an isolated farm and... well, you won't believe what happens to him in the subsequent hour. Joining the ranks is David Moreau and Xavier Palud's Them [Ils], a supposedly based-on-truth story (see the Press Conference extra below for more on this) that, despite its title similarity to Gordon Douglas's seminal 1954 science fiction film, has nothing whatsoever to do with giant ants.

At the core of this particular Them is a French couple named Clémentine and Lucas who are working in Romania – he's a writer and she's an English teacher and they're doing well enough for themselves to have rented a large and isolated countryside chateau, where they can unwind from work without being bothered by anyone. Except one night they are. Woken by noises downstairs, they soon find the house under siege from unseen figures and become embroiled in a deadly game of cat and mouse within its walls.

At its best, Minimalist Horror provides 90 minutes or less (you're pushing your luck if you go for longer with so little plot) of unpretentious, seat-grinding tension, a return to the pre-postmodernist roots of the horror thriller when scaring the audience was paramount, the sort of experience that can send you through a bag of popcorn in five minutes or have you biting your fingernails down to the flesh. At their worst they are all technique and no substance, the mechanics of horror cinema with no character identification (see My Little Eye for an example of this – the film starts shouting "Boo!" at you even before you even know who the characters are, let alone that they're sall arses).

Following a prologue involving two local girls, a stalled car and something nasty in the woods, Them almost invisibly aligns us with its Clémentine and Lucas before moving briskly on to the screw turning. In the middle of the night Clémentine wakes to hear not breaking glass or creaking floorboards, but the muffled sound of rock music, a genuinely creepy sequence that suggests someone – or something – is already in the house and doesn't much care who knows it. The inevitable "Oh no, don't go out there!" bit is rather well handled, but it's once the assault on the house kicks off that the tension is racked up. One particularly jarring scare involving a missing door dangle ensures that the audience remains on edge for a similar jolt for a good twenty minutes or so, as injuries are inflicted and the labyrinthine structure of the chateau keeps the couple on the move, and us unsure just where the invaders will pop up next. The claustrophobia is diluted a little when the action moves outside and into the grounds, but a combination of disorientating woodland, a wire fence that divides the couple and some atmospherically gloomy waste tunnels keeps the sense of suppressed panic ticking over. All good news, then. Well, not quite.

Despite our engagement with the plight of the characters and some very effective tension building, the lack of plot substance does make itself felt. This is partly due to the familiarity of the locations – big old houses and unkempt woodlands are well-worn settings for people-in-peril horror, and the film never quite achieves the sense of hopeless and lethal isolation that made Open Water so nerve-wracking. Them does have a last act twist in its tale, but alert viewers will spot the clues a lot, lot earlier, and the threat does not inspire the same level of fear once it has been identified, though it still provides the story with a suitably creepy ending.

Them also taps into a recent horror trend of landing American, English or western European characters in some dark and demented corner of Eastern Europe, where all rules of civilised society have been hacked to death and eaten raw.* It's them and us with more than a hint of xenophobia, and a curious throwback to Dracula and its ilk, which was written at a time when international travel was a luxury for the wealthy few and when it was just possible to believe that there really were monsters living in castles in distant Romania, a country that the general populace knew next to nothing about. In post-Charles Manson America, the horror moved into the house next door, but genre filmmakers appear to be once again putting fear of foreign lands and their different-from-us inhabitants back into the mix. This is perhaps a reflection of an increasing intolerance in western society, driven by a deluded sense of moral superiority over cultures they seem worryingly comfortable looking down on.

But despite all this, Them is still a sometimes supremely tense wind-up with just enough of a social subtext to echo on after the film has concluded. And with a running time of just 74 minutes and panic-pitched pace, there really isn't a dull moment here.

Them was shot on what looks like DV-CAM, but you wouldn't know it from the picture quality here. The 2.35:1 anamorphic transfer displays very good contrast and detail and has a look that is interestingly halfway between film and video. Digital grain and movement stutter is inevitably evident, but shadow detail is better than you'd expect for the source medium, especially given that most of the film takes place at night. Colours have been deliberately subdued and later are almost completely drained.

There's a choice between Dolby 2.0 stereo and Dolby 5.1 surround and 5.1 is definitely the way to go, the surrounds creating a more inclusive experience

Making Of (26:43)
Built around interviews with directors David Moreau and Xavier Palud and actors Olivia Bonamy and Michaël Cohen and some interesting behind-the-scenes footage, this brisk featurette takes us through the process of making the film and specifically the approach of both parties to their respective roles in the production. A particularly telling moment catches Bonamy in a moment of tearful despair at the punishment she has taken on the shoot.

Clementine's Ordeal (7:15)
An interesting though not in-depth look at the setting up and shooting of a scene that should not be revealed in advance of a first viewing.

Police Press Conference with Victim's Sister (1:40)
Hmm. As anyone who has seen the poster will know, Them is supposedly based on a real incident and the locations and characters are thus claimed to true to the original story. If this is the case then I can't be the only one wondering if maybe, just maybe, such dramatisation of a not so long ago event is crossing that exploitation line. The problem is that the whole 'based on a true story' thing is a favourite horror movie tagline that sometimes turns out to be fabricated hype. The brief extract from a press conference in which the victim's sister makes an appeal for information may seem genuine enough – and if it is then this should convince a few more that the filmmakers are in iffy territory – but the blurred-out face, the complete lack of details on the 'real' case elsewhere on the disc and on the official web site, and the absence of even a suggestion of such a link in the Making Of documentary (the directors go into some detail on the writing process) prompts me to smell a big, deceptive rat.

Footage Recovered  from original Location (0:58)
A "Boo!" promo thinly disguised as genuine location footage.

Interview with Composer Rene-Marc Bini (10:17)
A mildly interesting interview with the film's composer mixed with footage of  the recording of the film's score and sequences from the film played with the music only.

The Awful Truth
A textual essay on the social conditions behind a key aspect of the film's plot.

Marketing Campaign
Trailers and other marketing tricks, namely the UK Theatrical Trailer (1:17), 3 TV Spots (0:42), Theatrical Campaign Concepts (0:38), the particularly cheesy London Invaded by Them (1:32), a Promotional Fly Poster, a fake Neighbourhood Watch logo and Standee, which is a picture of a promo box.

A tense and very well executed frightener that could do with a little more meat on the plot bones, but it should certainly land the first-time directors more work, which was probably the main aim. Metrodome's DVD serves the film well enough, although a filmmakers' commentary would have been nice here. I'm still taking the 'based on a true story' claim with a pinch of salt, but that doesn't detract from the film's effectiveness.

* Other examples include Bruce Hunt's The Cave, Eli Roth's Hostel (both 2005) and Christopher Smith's Severance (2006). Severance is far and away the best of the three, wittily game-playing the situation while still delivering on the horror.