After his family's death, Yoo Haemin gives up on his dream of attending college because he can no longer play the piano due to a sudden hearing loss. While listening to someone's unfinished song he found on an old laptop, he is drawn by a scream from the upstairs neighbor and saves Shin Jeyeon from being assaulted. As this incident brings them closer, the two realize they have a shared experience of a parent's sudden death and an obsession with music, and they feel an inexplicable attraction to each other...