Researchers on the undersea laboratory Aquatica have genetically altered the brains of captive sharks to develop a potential cure for Alzheimer's disease. There is one unexpected side effect. The sharks are getting smarter. Which could mean trouble for the researchers. And lunch for the sharks. You can swim but you can't hide when a tropical storm floods Aquatica, plunging Samuel L. Jackson, Saffron Burrows, Thomas Jane, LL Cool J and the rest of the crew into a harrowing battle of wits against sleek killing - and thinking! - machines. Renny Harlin (Cliffhanger, Die Hard 2) directs, squeezing nerve-jangling suspense and thrills from a film that's a monster movie, a chase movie, a movie that snaps hold and won't let go. Dive in.