In 1945, the Portland-class cruiser , commanded by Charles B. McVay III (Nicolas Cage), delivers parts of the Nuclear weapon that would later be Atomic bombings of Hiroshima and Nagasaki during the ending of World War II. While patrolling in the Philippine Sea, on July 30 in 1945, the ship is torpedoed and sunk by the Imperial Japanese Navy (IJN) submarine ''Japanese submarine I-58 (1943)'', taking 300 crewmen with it to the bottom of the Philippine Sea, while the rest climb out of the ship and are left stranded at sea for five days without food and water in shark-infested waters.