Keep your wetsuit on

Thriller 'Open Water' takes a bite out of suspense genre

Among people I know who've seen the coming-attractions trailer for "Open Water," the split is about even.

Roughly half find the movie's premise - two vacationing scuba divers stranded in a shark-infested sea when their boat returns to shore without them - so unusual and scary that they're eager to view it on the wide screen.

The others can't imagine why this is worth the price of a movie ticket.

Two heads bobbing in the waves - and bobbing and bobbing - until it's time for the closing credits? "Give me 'The Manchurian Candidate' for my hard-earned dollars," they say. "Or even 'Catwoman,' which at least has Halle Berry to look at!"

I've been among the curious viewers raring to dive in, if only to see whether writer-director Chris Kentis could sustain such a stripped-down situation for the length of a feature film.

He does it marvelously well, helped by the facts that "Open Water" is relatively brief - about 80 minutes - and that the first quarter (approximately) is taken up with setting the scene.

So effective is the suspenseful part that I wish the movie were even shorter - with the opening trimmed and the divers dunked without delay.

I'm not suggesting this because the movie feels too long, but because its filmmaking is so richly economical and its action is so psychologically intense. It could have been even more squirm-inducing if its tension were distilled as radically as possible - pushing its minimalism to the max, you might say.

This aside, "Open Water" is the season's most gripping thriller, thanks to its single-minded vision and the keenly focused acting of Blanchard Ryan and Daniel Travis as Susan and Daniel, respectively. It also helps to know the movie is based on a reconstruction of actual events, and that it was filmed in real ocean waters - with real sharks.

Some viewers have already praised the picture - or dissed it - as a "Blair Witch Project" of the briny deep. I think it's worth a dozen "Blair Witch Projects," with much more harrowing psychology and pithy dialogue. It's a bone-chilling plunge into no-holds-barred storytelling.

• Rated R; contains some nudity and scenes of extreme peril.