Hyun-Jung, a woman living alone nervously watching the news. Seung-Jin, a middle schooler trying to raise his failing grades by doing volunteer work. Hyun-Su, a woman trying to find a friend of the opposite sex through a dating app. Hoon, a man who finds a mysterious letter with written instructions to find the woman who penned them. Gee-jin, an unemployed man with a one-sided crush on the stewardess next door. Yeon-jin, a musician and part-time worker at a convenience store who lives a crappy shitty life, dealing with rude customers daily. These six people's lives intersect in unexpected and disturbing ways over the course of four days..