Plot
Each of Jun and Tae-hyeon is one of the best skilled divers in the SSU. They are not only the best friends but also the rivals. One day, training master Gang Su-jin appears in front of them. She was the former girlfriend of Jun and also one of the companions in the SSU. The meeting of these in 3 years becomes filled with a complex atmosphere amidst the precious friendship and the feelings of love that they cannot express. At last, the main operation of the Navy, Mink Operation starts. In the middle of carrying out the operation, the Hanbando made an emergency landing at the deep sea. During the process of rescuing the survived, Su-jin becomes trapped herself. Jun and Tae-hyeon jump in to the deep sea of 187 meters that no one ever had challenged…
