The great adventures of life and human connections in contemporary Korean society, following a formal baseball player, a sleepless student, a new hangman, an imprisoned gangster, and a mysterious father and daughter.

Su-kyung is a young adult who is struggling to fit in at work due to her introverted nature. She signs up for an SNS service, where she begins to communicate regularly with a stranger named Jeong-yeon. Having no other friend, Su-kyung opens up to Jeong-yeon, and the two of them finally agree to meet up in person.