I loved this film, and so does Heather Havrilesky at Salon and Don Lewis over atFilm Threat.

Heather: If you haven’t rented “Jaws” or watched the Discovery Channel’s “Shark Week” for a while, you might have conveniently forgotten about our friends the sharks, with their razor-sharp teeth and their curious little quirks. Enjoy this blissful lapse while you can, because director Chris Kentis is about to refresh your memory. The heart-stopping realism of his movie “Open Water” has the most reserved crowds at Sundance gasping and cringing in horror. Based on a true story of a vacationing couple scuba diving and abandoned in the middle of the ocean, “Open Water” has a straightforward style that pulls the viewer, kicking and screaming, into the narrative.

Don: “Open Water” taps into everyone’s fear of being lost. Everyone knows how that feels and that fear is what made “The Blair Witch Project” so stomach churning. It’s also what makes this film so gut wrenching. Well, that and a whole bunch of huge sharks.