One winter, a note circulates spreading rumors, stirring up the Korean Military Academy. Jiwoo, who despite his confident attitude hasn’t secured a recommendation letter, and Hoon, a graduate dreaming of assisted suicide in Switzerland, encounter someone else at the Academy during the quiet night.
Na-mi and Sun-woo, the outcasts in school, plan to commit suicide instead of going to the school trip. On the moment of success, they find out that the girl, Chae-lin, who made their lives miserable is living a new happy life in Seoul. So, they decide to make revenge before ending their lives. However, when they finally spot Chae-lin, they see a good-hearted girl in front of them which makes their plans go awry.
Su-kyung lives with her daughter Yi-jung. They don't quite get along, though. Su-kyung is too hot tempered, while Yi-jung is slow and passive. After having a fight one day, Su-kyung runs over Yi-jung, who thinks she did it on purpose. Their clash ends up in court.
A couple decides to adopt a child to overcome the loss of their third child whom they lost to an accident. They adopt a boy who is visually impaired, hoping that raising him would make up for the insufficient love they gave to their lost child. The adopted boy has an acute sense and begins to notice that there is another presence in the house. He discovers that the presence is a boy who died a year ago and summons him back to the family. The mother gets obsessed with communication with her lost child. The father and the other children believe the adopted boy is lying, and start to fear the mother's growing obsession toward her lost child and the adopted boy. The children feel compelled to tell their parents about the secret about the lost child, which changes everything for the family.
Kyung-ah works as a caregiver and lives alone. The only one she can rely on is her daughter, Yeonsu, but it's hard to see her after her independence. Meanwhile, Yeonsu, who was suffering from his ex-boyfriend, argues with him again and heads home. After Yeonsu left, Kyung-ah receives a shocking message.
Based on Lim Solah's novel of the same title, Snowball focuses on the friendship between three girls who are united by frustration with the mundane routine of high school life and its associated authority figures, only for their bond to be severed by otherwise different natures.
A sheep farmer whose remote and quiet life is disturbed by the arrival of both his lover and his twin sister.