Jung Mu-young (
Park Hae-jin) was left by his birth mother under the care of Kim Tae-shik (
Jung Han-yong) and his wife Park Myung-ja (
Jung Ae-ri) when he was very young. His mother promises to come for him later, but she never does. The Kim family raise Mu-young like he is their own son, but never change his family name because they think his birth mother might come later to pick him up. Despite the lack of money, Myung-ja manages to keep the family together; moreover, she never once treats Mu-young any differently than her biological son. Still, having a different family name from his older brother Kim Sang-hyun (Lee Joo-hyun) makes him run away from home several times. Mu-young is outwardly rebellious, unforgiving, and in constant conflict with his family. He keeps an emotional distance from them, for fear of getting hurt one day. At school he meets the cheerful and kindhearted Seok Ji-soo (
Han Hyo-joo), who not only values her family greatly, but also goes out of her way to help others. Thinking too highly of Ji-Soo and too lowly of himself, and aware of the possible negative reaction her family might have toward his confession to her, he tries to keep a distance between himself and Ji-Soo. As a grown up, Ji-soo begins working for Myung-ja's stepsister, Park Myung-joo (
Yoon Hae-young), and learns that she and her single father, Seok Jong-hoon (
Hong Yo-seob), are in love. She fully supports her father's newfound romance. She is also seeing a rich family's son who wants to propose to her.
Heaven & Earth tackles the issues the modern family faces, such as the difficulties faced by stepparents and stepchildren; conflicts between biological and adoptive parents; the aftermath of a remarriage; and the high divorce rate among the younger generation, and resulting involuntary childcare from their grandparents. ==Cast==