Don't go into the woods, warned The Blair Witch Project. Don't go up the mountain, warned Touching The Void. Now another hugely suspenseful low-budget thriller delivers its doomy admonition: don't go back into the water.
The best movies kid us into thinking we have mastered nature, that we are born survivors, and then suddenly reveal how perilously thin is the crust of civilisation we've been treading on. So it is in Open Water. Armed with digital video cameras, American Chris Kentis has taken to the high seas and delivered a tense essay in human vulnerability and fear. I spent long periods of this relatively short film holding my breath.
Kentis, who wrote, directed and edited the picture, is careful to set it up in an unassumingly humdrum way. A thirty-ish couple, Daniel (Daniel Travis) and Susan (Blanchard Ryan), are loading their car in preparation for a much-needed holiday. They're both somewhat frazzled by their jobs, and haven't found time to unwind. Once they get to their resort hotel one senses a bit of needle in the air: in bed, he tries to nudge her towards sex, she's "tired" and wants to talk; in the middle of the night, he clicks the light on and uses a rolled-up magazine to go stalking a mosquito. So far, so familiar: there's not much wrong with them other than the difference between a man and a woman.
The morning finds them in a better mood: they're aboard a chartered boat that's taking them, and 18 other guests, for a scuba-diving session in the open sea. Soon they are swimming underwater amidst trumpet fish, catfish, and moray eels, while a fearsome-looking barracuda shimmers past them. Meanwhile, back on the boat, the guide who has counted off 20 returned divers - miscounted, as it turns out - pulls up the ladders and heads back to shore.
Ten minutes later Daniel and Susan bob to the surface to find themselves absolutely alone, in open water, and not a clue as to where or why the boat has gone. "Think it's time to swim?" Susan asks. "Swim where?" David replies. At this point Kentis has his camera trained on two people in a vast expanse of water, and that is more or less where it stays for the remainder of the film. Yet he builds a quite excruciating tension from this simple geometry. At first, the stranded couple are flummoxed by the boat's disappearance: maybe they surfaced at the wrong spot. But Daniel had marked a coral formation - he's "90 per cent certain" that they're in the designated area. As the hours slip by, they try to keep their spirits up with a movie trivia game, and wave their arms whenever they see a boat - but they're too far away to be seen. Slowly, but slowly, the full horror of their situation dawns. Neither wants to mention Jaws, but that fin they just saw flash by belongs to a shark. They begin to paddle backwards, while the slap of the sea water and their own laboured breathing develop an ominous cross-rhythm.
The camera, ducking into the hypnotic blue of the deep, makes us ask how long it will be before a shark decides to take a bite of the dangling, flippered limbs in front of it. Several times a grey spectre circles about them, brushes past, then disappears. Susan, having fallen asleep, wakes to feel a burning pain on her leg; Daniel dives to investigate, and sees a neat row of teeth-marks along her calf.
In the cause of realism Kentis and his wife, Laura Lau, worked with experts to film reef sharks, and manipulated their movements around the two actors by throwing chunks of bloody tuna into the water. There are no special effects here, just nature red in tooth and fin. (The actors, who perhaps wondered what they'd got themselves into, wore chain mail beneath their wetsuits). "I don't know what's worse," says Susan, "seeing them or not seeing them." I knew how she felt.
Eventually, exhausted with misery and dread, they do what every couple on holiday would do when something goes wrong: start apportioning blame. Why didn't you ensure we surfaced on time? How has this become my fault? Whose idea was this vacation anyway? The recriminations fly back and forth, and one feels a weird comedy in the spectacle of a couple, adrift in the middle of the ocean and in grave danger of being chomped to death, still managing to have a domestic squabble. Susan, as if clinching the argument once and for all, shrieks, "I wanted to go skiing!" You have to laugh.
The precise location of the calamity is not specified - we presume it is somewhere in the Caribbean - but that is made to seem irrelevant. The unspoken star of the movie is Nature herself, boundless, immemorial, indifferent. The disconcerting irony is that, while the ocean reduces them to the level of shark bait, the couple become more humanly interesting in extremis. We hardly knew them when their ordeal began, but by the end we feel almost bonded. This fiendishly skilful movie will leave you stunned, nerve-jangled, and possibly more inclined to prefer an open sewer to an open sea.