With only a few weeks of the drama "Shark" left, viewers may already be wondering what will replace it. That series, "Good Doctor," will take place inside the pediatric department of a university hospital and stars Moon Chae Won, Joo Sang Wook, Joo Won and Kim Min Seo.

Joo Won plays Park Si On, a pediatrician who despite his developmental disabilities is a medical genius. He is a gifted doctor but has trouble with other areas of his life, such as relating to people socially. The character has overcome much prejudice to achieve his goal of becoming a pediatrician.

To fully engage in his role, Joo Won researched the character's disability and other medical issues by reading books and consulting with experts.

According to a representative from the production company, "Joo Won is trying something he's never done before and he's very passionate about it."

His most recent role was a novice spy in "Level 7 Civil Servant" and before that he played the masked avenger in "Bridal Mask."

Moon Chae Won will play Cha Yoon Seo, a pediatric surgical fellow. She is studying for her role by reading books, getting lessons and watching documentaries. Moon Chae Won previously played Seo Eun Gi in "Bad Guy" and Lee Se Ryung in "The Princess' Man."

Actress Kim Min Seo will play Yoo Chae Kyong, who works in the hospital's planning department and is the daughter of the hospital's director. Kim Min Seo starred together with Joo Won in "Level 7 Civil Servant." She also had roles in "Sungkyunkwan Scandal" and "The Moon Embracing The Sun."

Kim said she took on the role because she read the script and loved the intense interactions between the characters.

"Yoo Chae Kyong is a privileged woman who is smart and practical," said Kim. "She's a complex character."

Yoo Chae Kyong is also the fiancée of pediatrician Kim Do Han, played by Joo Sang Wook. While Kim Do Han is engaged to Yoo Chae Kyong, he has a crush on Cha Yoon Seo, which is bound to create some drama. Joo Sang Wook played Yeo Ji Hoon in "Special Affairs Team Ten, Season 2."

Kim Young Kwang, who appeared in "Birth Secret," plays a resident who befriends Joo Won. Ko Chang Seok plays Jo Jeong Mi, a pediatric male nurse, who was formerly a tough guy,

The series has been described as a heartwarming medical drama. It will air August 5.