Researchers aboard the floating laboratory Aquatica have been playing God and now, the terror of Judgment Day has arrived.

Dr. Susan McAlester’s (SAFFRON BURROWS) experiments are on the verge of creating medical history. Using mako sharks, one of nature’s fastest and most perfect killing machines, Dr. McAlester hopes to find the key to the regeneration of human brain tissue. But to reach her goal, she has violated ethical codes, genetically re-engineering the DNA of the sharks. Making them smarter. Making them faster. Turning them from dangerous predators into predatory monsters.

But McAlester has more to worry about than the deadly specimens at the center of her studies. Her questionable methods have put a strain on the relationships with her fellow Aquatica crew members, chiefly shark expert Carter Blake (THOMAS JANE) and Sherman "Preacher" Dudley (LL COOL J). Escalating the stakes, the researchers’ skeptical financiers are nervous and have threatened to shut down the off-shore facility on the eve of a round of key tests.

Under the watchful eye of financial backer Russell Franklin (SAMUEL L. JACKSON), Susan and her team successfully extract brain tissue from the largest of the mako sharks, only to watch in horror moments later as the shark exacts a revenge that results in irreparable damage to the research facility. With a tropical storm swirling around the now sinking Aquatica, the scientists and workers find themselves stalked by the terrifying new generation sharks—fighting against the deadly monsters they helped to create.