The Heirs

Cha Eun Sang is a 17-year-old daughter of a mute housemaid of a wealthy family whose 17-year-old son, Kim Tan, she meets while looking for her never-do-well sister in the United States.

After being left stranded by her sister and having her passport taken away by the police, Cha Eun Sang accepts Kim Tan's offer of staying at his house.

While trying to delay Eun Sang from returning to Korea, Tan takes her with him to meet his half-brother, Won, who has arrived in the U.S. on a business trip. Meanwhile, Eun Sang's mother, Hee Nam, accidentally overhears her employer's mistress, Ki Ae, talking about getting rid of his second wife.

Eun Sang and Ra Hael, Tan's fiancee who came to visit him in the U.S., return to Korea. Upon returning home, Eun Sang discovers that her mother has been evicted and has moved into her employer's home. Missing his family and Eun Sang, Tan returns to Korea, much to Won's dismay.

To his shock, Tan discovers that Eun Sang and he are living under the same roof. He shadows her as she helps her mother with her household duties. Unbeknownst to him and his brother, their father is keeping taps on their respective relationships with Eun Sang and Hyun Joo, and in response, has offered Eun Sang a scholarship to Jeguk High School, a school for the elite and wealthy.

Eun Sang and Tan begin their first day at Jeguk High School. While Eun Sang is introduced to the social class system of the school, Tan clashes with his former best friend, Young Do. Meanwhile, Tan and Won's relationship worsens as their father decides to introduce Tan to his company's board.