A heroic doctor steps in to help a distraught boy. Intern Gang Dong-ju helps Dr. Yun Seo-jeong with emergencies at Geosan University Medical Center.

Dong-ju wonders whether hard work is enough to get ahead. Doldam Hospital gets a new doctor in general surgery. Seo-jeong sees a face from the past.

Dong-ju questions Teacher Kim's ways, despite his awe-inspiring skills. Seo-jeong must deal with the ramifications of her actions.

When Doldam gets a surprise, everyone tries to cope. Dong-ju wants to know where he stands. Teacher Kim gets what he wants -- for now.

A patient comes first -- no matter what. Seo-jeong gets an unexpected pep talk. Teacher Kim's compassion proves to be multilayered.

During his trip to the main hospital, Teacher Kim leaves an impression — especially on three young doctors who find themselves in his hospital lobby.

Teacher Kim shocks Seo U-jin with his unconventional approach to saving a high-ranking official, and bans Cha Eun-jae from assisting his surgeries.

Teacher Kim makes demands of his own. Myeong-sim shows the staff how it's done. Associates from Seoul stop by Doldam. In-beom makes a gut call.

Do Yun-wan creates chaos by bringing his own team of doctors. U-jin's participation in Park Min-guk's surgery sparks a misunderstanding.

U-jin gets caught in the middle of two feuding teams of doctors when the family of a patient threatens to sue for malpractice.

New doctors get a taste of their first Friday at Doldam Hospital. U-jin refuses to treat a patient who triggers his childhood trauma.

Dong-ju finds that he's no match for Teacher Kim and becomes desperate to leave. Doldam receives a VIP visitor. Seo-jeong gets a new role.

Being principled may be relative. It's all hands on deck after a major highway accident. Dong-ju tries to find out more about Teacher Kim's identity.

Dong-ju gets bad advice and faces the consequences. Seo-jeong gets put on the spot. Yun-wan dials up the pressure but Teacher Kim pushes back.

Min-guk becomes determined to turn people away from Teacher Kim. A situation Eun-jae tries to mitigate takes a turn for the worse.

Dong-ju makes a call -- to Chairman Shin. Teacher Kim reminds Yun-wan of the importance of basics. Seo-jeong vexes an old mentor. It's Friday at Doldam.

The staff starts preparing for Chairman Shin's surgery and Seo-jeong gets her big chance. Doldam may have an epidemic on its hands.

Teacher Kim leads his team in saving two critical patients at the same time. Eun-jae steps in to protect a woman from her abusive husband.

A recruiter with bitter resentment for U-jin tries to tempt staff members to leave Doldam Hospital. Eunjae's mom asks for a favor.

Yun-wan wants to know if Dong-ju is on his side. A soldier goes missing. Seo-jeong doesn't back down, but Teacher Kim shows her how it's truly done.

In a twisted world that demands blind obedience to its rules, there's no room for those with integrity and ability. Shin's surgery gets complicated.

Yun-wan makes sure that old wounds don't lie dormant. The furtive reporter keeps snooping around. Dong-ju confronts Teacher Kim about the past.

Min-guk asserts his authority by restructuring the hospital staff. U-jin is stunned to learn which surgeon was behind a faulty operation.

Eun-jae panics when she runs out of medication from Teacher Kim before surgery. U-jin gets coerced into leaving Doldam Hospital.

The inspector from Geosan tries to stop the Doldam staff from treating patients. But there's a multicar accident -- and a drunk driver at the scene.