Halo, the greatest musician of his time, gets into a car accident on his way to the Grammy Awards. When he comes to, he finds himself in the body of a young Korean boy named Noh Hae-Il. He is left in a place where the surroundings and the times are different. After confirming that Noh Hae-Il's English name is Halo, he feels a strong sense of destiny. Halo enters Hae-Il. He demonstrates his genius even in this era.

(Source: Naver, translated)