This is a pretty bad movie that (I think) knows it's a pretty bad movie.
What keeps it from being even worse and entering into the useless "torture porn" genre is its PG-13 rating, which teeters on the brink of "R" territory throughout. Honestly, it's just another stalk ‘n' slash. And this time you pretty much know who's going to make it and who isn't.
You have another bunch of college-age kids (these are from Tulane University), this time on a trip led by Sara (Sara Paxton). The troupe includes the smart but shy pre-med student Nick (Dustin Milligan), who has eyes for Sara but is afraid to make his move, a video game player (Joel David Moore), a football star (Sinqua Walls) and his girlfriend Maya (Alyssa Diaz). They take off to a remote Louisiana lake. (I have to give the screenplay credit for establishing that the location is so out-of-the-way that there is no cell phone reception. Good thinking.)
And so off they go, girls eying the guys and vice versa. They take off on a fun chase scene as they are pursued by the local sheriff (Donal Logue), who turns out be a beer-swilling fellow who has known Sara for years. Two other townsfolk who also have known Sara for years are Dennis (Chris Carmack) and his hillbilly sidekick Red (Joshua Leonard, "The Blair Witch Project"), who right away start picking fights with Sara's friends. Obviously, Dennis and Sara go back a long way, and, even more obviously, Dennis has some kind of score to settle.
Of course, no one realizes that the only threat doesn't come from the hillbillies. But exactly what's in the water and how it got there will be explained in due time. Meanwhile, the young people meet their demise one at a time.
Nothing can beat the first "Jaws," even with the addition of 3-D imagery that's good enough to serve up a couple of "Boo!" moments or a music video with the ensemble that plays post-credits.
I really hate to consider this an educational film, but I have to give credit where credit is due: I never knew about the cookiecutter shark that does indeed swallow its own teeth.
But you don't need to see this to learn more about sharks. Just head to the Putnam IMAX for the terrific "Sharks 3D," which is well worth seeing.