After losing his wife five years ago, Sang Tae has been dedicated to his two children and his in-laws, who treat him like their own son. He never expects to find someone who will make his heart beat again. Mi Jung divorced her adulterous husband three years ago, but has yet to tell their three children. She has numbed herself from the struggles of raising her children alone while working. As these two begin to find love again, a tempest is brewing as three sets of in-laws and five children learn to become one family.