Kyung-chul has been worrying about their grandsons. None of the three is contemplating getting married. Seeing their parents anxious about their sons' hesitation to start a family, he finally proposes an idea, a.k.a. Operation Three Brothers' Marriage. He gathers the grandsons and declares that the first one getting married will get a house. Soon the competition begins: only, the three's goal is not to get the prize but to defeat others.