Kim Tae-yang is a physician and Choi Yoo-ri is a broadcasting producer. Choi Jae-min is a dandy-ish executive at a clothing company and Kim Saet-byul is an unwed mother. Kim Woo-joo is much younger than Hong Mi-rae. As these three couples fall in love, they explore issues of age difference, blood ties and adoption, and wealth and poverty.