Korean action film. Two Naval Academy deep-sea diving cadets both fall for Su-Jin (Shin Eun-Kyung), an attractive and ambitious Naval officer. This causes a rift in the two men's friendship. The three are later reunited in the Special Salvage Unit, an elite underwater rescue team of the Korean Navy. The awkward trio must now work together and survive the treacherous situations of their life-threatening mission - to rescue the crew of a submarine that has become stranded 1000 feet below the surface of the unforgiving ocean.