Hyun-su and Soo-jin are newlyweds. Seemingly out of nowhere, he starts talking in his sleep. “Someone’s inside.” From that night on, whenever he falls asleep, he transforms into someone else…

During the 1990s, hardworking Mi-soo and optimistic Hyun-woo meet at a bakery and fall in love while exchanging stories on a radio station, but while their paths keep crossing, the…