In 2023, Eun Gyeol, a high school student and a CODA (Child of Deaf Adults), has a deep passion for music. By day, he excels as a diligent student, but by night, he transforms into a guitarist for a band. His life takes an unexpected turn when he discovers a peculiar and captivating music store that transports him back to 1995.
There, he encounters his father, Ha Yi Chan, as a high school student. Yi Chan thinks Eun Gyeol is crazy when he addresses him as βdad.β To make matters worse, Yi Chan appears to be infatuated with Se Kyeong, a cold-hearted cellist, instead of Cheong Ah, Eun Gyeol's future mother.
Determined to set things right, Eun Gyeol joins a band led by his young father.