Nam Hyun-soo (Cha Tae-hyun), a single nobleman with a good life, was once a failed singer. After turning 30, he ushered in the second spring of his career. The talk show hosted by Hyun-soo is very popular, especially the story of single mother Jingnan looking for her biological father in recent times, which has set off a climax of soaring listening rates. One night, when Hyun-soo was waiting to spend a romantic night with his girlfriend, a pair of uninvited guests ruined it all. The visitors were Jingnan (Park Bo-young) and her 6-year-old son Jidong, and the father she was looking for turned out to be Hyun-soo! It turned out that Hyun-soo had fallen in love with a neighbor girl who was 5 years older than him when he was in the third grade of junior high school. This only love and the only physical pleasure led to the birth of his daughter. The lover at that time concealed the fact of pregnancy after breaking up, and Hyun-soo left his hometown to pursue his dream. The arrival of his daughter and grandson made this childish man who was used to single life feel troubled. More importantly, in this chaotic and complicated entertainment industry, such a scandal would destroy Hyun-soo's career that he had worked hard to build. How should he face all this suddenness?