Lee Jong Suk of "I Hear Your Voice" and Park Hae Jin, currently appearing in "You Who Came From The Stars," have signed up to play roles in the upcoming series "Doctor Stranger." Lee Jong Suk will play a genius North Korean doctor who is treated unfairly when he works at a top medical institution in South Korea.

Sounds good. But despite the star cast, being set in a hospital is not always the prescription for k-drama success. Last year, two medical dramas scored very differently in the ratings.

"Good Doctor," starring Joo Won, Moon Chae Won and Joo Sang Wook, was a ratings winner, averaging Nielsen ratings of 17.2 percent. Another medical drama, "Medical Top Team." also had an impressive cast, with Kwon Sang Woo, Jung Ryeo Won and Joo Ji Hoon. But that drama was one of the year's worst ratings failures averaging 5.5 percent.

Why did one medical drama succeed while another failed?

Each drama had medical emergencies and dramatic conflict between the hospital's medical personnel. Conflicts were created when characters in both dramas prioritized politics and self-interest over saving lives.

But "Good Doctor had something extra, a completely relatable character who overcame overwhelming odds to eventually be recognized for his true worth. And it was a little different as the genius surgeon was also suffering from autism spectrum disorder. His disability made it difficult for him to communicate with others. Viewers felt sympathy for Joo Won's character and were intrigued by his predicament.

This year, "Emergency Couple" is the first drama to be set in a hospital. Their doctor-speak has been fairly authentic and the emergencies are genuinely dramatic. But what makes that drama work is the comic relationship between Choi Jin Hyuk and Song Ji Hyo. In a life and death setting, they can't waste time trashing each other and might even remember how much they once liked each other.

So far "Doctor Stranger" sounds like it will borrow a page from "Good Doctor" by making its main character a man out to prove his worth despite the odds. Lee Jong Suk has had lots of practice at making audiences sympathize with him in his "I hear Your Voice" and "School 2013" roles. Another plus is that PD Jin Hyuk, who is responsible for directing "City Hunter," "Prosecutor Princess" and "The Master's Sun" will direct the drama.

What do you think of the odds for this medical drama's success? Let us know.