Se-ha who is physically handicapped and Dong-gu who is mentally handicapped are not their own brothers. But while living 20 years together, the two became indispensable to each other. One day, the mother of Dong-gu suddenly visits him and acts as his guardian.
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.
A debt collector who looks intimidating, but actually has a warm heart, ends up becoming the guardian of a child, who has been left behind as collateral by her illegal immigrant mother.