This Roger Corman produced flick begins with stock footage of glaciers falling into the ocean, then cuts to computer animation of something that looks like a mighty big tadpole emerging out of the ice. Then, "Three Years" later a diver is eaten by something mighty big. And it looks prehistoric.
The main story begins in Mexico, where Trace McGraw (Eric Balfour of SKYLINE, SIX FEET UNDER) has returned, giving tours on some guy's yacht for the summer. It seems as if he's fled something. He meets up with an old friend who is part of the local police and we get the sense that Trace indeed has a shady past. There's also a girl who works in a bar, who is interested in him. Out on the water, Trace witnesses some people being eaten by a huge fish. He does some quick research on the internet and is convinced this is a prehistoric animal. When he tells this to others they don't believe him-- until it's too late (of course).
While I found the story boring the monster actually looks pretty cool. My favorite scene is when it eats a para sailer. And producer Roger Corman has an acting bit s Dr. Reeves, who knows all about the prehistoric critter.