Former teen idol Nam Hyeon-soo is now in his thirties and working as a radio DJ. One day a young woman named Jeong-nam shows up and claims to be his own daughter. She also has a son whom she claims to be Hyeon-soo's grandson. Their relation is proven via DNA tests by Hyeon-soo's brother. This leads to Hyeon-soo attempting to avoid a scandal concerning him having children "unknown" to the media.
KO