Sharks lead to a man vs. beast showdown in the North Atlantic. Huge great white sharks have been spotted in Gloucester waters. Captain Kevin is on full alert when a great white slams into the side of his fishing vessel Christina. When a harpoon line gets tangled in the Pin Wheel's propeller, Captain Tyler has no choice but to get in the water. With great whites able to detect trace amounts of blood from up to three miles away, he and his hard-won tuna catch are at high risk.