Deep blue sea: Return to the deadly deep blue sea! In Deep Blue Sea, you can swim but you can't hide when a tropical storm floods the undersea laboratory Aquatica, plunging the crew into a harrowing battle of wits against sleek killing--and thinking!--machines. In Deep Blue Sea 2, 19 years later, a shark conservationist is shocked to learn that the company is using the most lethal predators in the sea as its test subjects.