Water Ghost.

Three unattractive guys named Ha-neul, Chan-hong and Su-ho go on a trip to Haeundae beach. Chan-hong is excited in the hope of meeting some girls. Su-ho says he knows the place with a lot of girls, but it turns out to be a restricted area not open to swimming. After a disappointment, they turn their minds and decide to have fun by themselves. And then, a beautiful woman passes by, and the three guys try to be close to her. On that night, they visit the woman's tent and disappears one after the other.