It starts so tokenistically - a bunch of silly young pretty tourists go somewhere they shouldn't, and shit goes down. Yet there is so much more going on in The Ruins than a cursory glance would indicate.
The titular ruins are a single Mayan pyramid that a group of mixed nationality tourists head towards. It's off the beaten track, in no known guidebooks but a chance encounter with a pleasant German backpacker whose brother is an archaeologist leads a core group of four Americans, the German and his Greek friend to the pyramid, where they are swiftly confronted by locals speaking a dialect none of them can understand. For reasons that are not immediately obvious, the tourists are all shepherded onto the pyramid and blocked off from leaving by the threat of death. With only a day's worth of water, practically no food, and tension simmering between the group things swiftly degenerate. To make matters worse, the ancient Mayans abandoned the pyramid for a reason...
The thing that impressed me the quickest about the film was the easy way it introduced the audience to the group dynamics. Like a thousand other horror movies before, the core group of Americans are all white, all pretty, and all presumably wealthy middle class types. Yet in just a few minutes we got a handle on how they feel about each other - the girls' friendship, the guys' relationships to the girls and subsequently by association to each other... the movie was efficient at showing what a group of travellers are like, with all the amicable surface level relationships that disguise the fact that it's a friendship of convenience, of people from similar backgrounds in an unfamiliar place. When things degenerate on the pyramid, there is a logical progression that flows naturally from the relationships established at the backpackers resort at the beginning of the movie.
The horror - what comes to hunt them - is foreshadowed well, and whilst you'll figure it out early and easily, I won't spoil the reveal. For all that you might see it coming, the film dealt with it extremely well and intelligently, giving the tourists the clues to the situation they're in. While the audience can make the connection between disparate evidence, the characters don't necessarily have access to the same points of view, and so when they figure out what's going on it all makes sense.
Most of the movie occurs in bright daylight (the film was shot on the Gold Coast hinterland - nice Mexican Gum Trees!) which in the hands of clumsy filmmakers would be its undoing. The film as I said though is handled well, and the horror comes shining through even in the harsh light of day. The gore effects are all handled prosthetically (which I infinitely prefer to computer animated gore which retains a slightly unrealistic sheen in all occurances I've seen of it) which lends gravitas and horror to both the viewer and the performer - you can see the actor's responding very realistically to every cut, ever wound, every nasty bump.
The film does have a few missteps - for all my praise of a logical character development, there are a few moments where the film leapt well away from the confines of logic and did something inexplicable. There are some animated sequences of the threat as well that are just jarring - the film is at its best rooted in practical effects, and would have been better staying with them alone.
At the end of the day though, the performances are all credible (which is a cut above for the genre, sad to say), the practical effects are superb, the script is well composed and thought out, and the production design is simply phenomenal. Being that somewhere between 80 and 90 % of the film takes place on a single pyramid, it has to be might compelling - and the filmmakers do it, they make it compelling. Single location films rely on the location almost being as much of a character as the performers within it - and The Ruins succeeds in marrying performance to location. A sophisticated piece of horror filmmaking. And Ben Stiller of all people got it off the ground!