They say that the medical intern has the lowest rank in the doctorly ladder in the hospital. They are often the most dispensable and insultable members of the medical staff, and everyone humiliates them in their job, including even the nurse. And Yeonhee is a surgeon-to-be, one of the best graduates of the SNU medical school. She heard some of her seniors in med school saying that intern year is the most horrible phase of their life, and that she needs to prepare herself.

Yeonhee only wishes that she can finish her five-year resident program smoothly, but she never expects that her days are more than just an intern's crisis and belittling seniors, especially when it involves Oh Sehun, a certain senior resident slash cardiovascular fellow whom she looks up to the most, also the nurses' favorite guy ever, named Dr. Zhang Yixing; a nowhere-school-graduated MD slash the famous Youtuber who everyone thinks as the cutest little sheep in town although he's no better than a second-year medical student in term of theory knowledge.

Love story and mystery, what will it be when both mix into the frame?

One can only guess.