Seven girls become good friends in high school, then events pull them apart for 25 years. When one of the friends lies dying in a hospital, she wishes to see each of them one last time.

Online fashion model Hyo-jeong faces imminent threat of being unemployed because of the younger and more fashionable generation coming after her. While relying on surgical procedures and treatments, Hyo-jeong hears about a mysterious yoga class that helps make perfect body shape from her old high school classmate, Ga-yeong. Hyo-jeong eventually attends the yoga class with three classmates: Mi-yeon, a boxer who failed to keep her body fit, Ji-won, who has unstable mental condition, and Ye-na, a movie star who is morbidly obsessed with her appearance. Meanwhile, police start to investigate the enigma behind this yoga class after finding out that a murder in the neighborhood was committed by a woman named Bo-ra, a former yoga class student.

Oh-Gwang is vicious real estate broker. One day, he gets into an accident while driving on a mountain path. Two days later, he wakes up. Oh-Gwang finds himself at the home of Mr. Jang, which is located deep in the mountain. Oh-Gwang was saved by Mr. Jang’s family. The family consists of Mr. Jang, his wife Yeon-Hee, son Hyun-Seok and daughter So-Hee. They are very nice to Oh-Gwang, but something about the family is suspicious. The family might be hiding something from Oh-Gwang.

A class of students stays at school for a camp in an elite study group to finesse theirs and the school's grades. Upon the first night, the swimming coach is found murdered. As the students try to figure out what happens, a voice informs them that if they don't figure the murder out, students will begin dying in quick succession.