'Shark Night 3D' Trailer Has Bite

Watch what happens when salt water sharks attack.

You're either into movies that show a bunch of hot teens getting picked off by sharks in a salt water lake or you're not. 

Just know this: you're in the hands of David Ellis, a guy who knows how to make scary be fun. He did Final Destination 2 and Snakes on a Plane.

And for a movie that comes out at the end of summer, this could be what is needed on a sweltering day.