This is a decent killer shark movie, though somewhat lacking in suspense. A group of scientists, trying to find a cure for Alzheimer's disease, are doing experiments on sharks' brains--but in order to do this they've had to make the sharks larger and their brains bigger. The three mutant Mako sharks rebel and trap the people in their underwater laboratory. Then, it's a matter of them escaping before the sharks can get to them. The most surprising thing about this movie is that it kills off some of the main characters, something you don't see very often in a Hollywood flick.