Five friends whose friendship goes back to their days in med school are brought back together when a phone call interrupts each of their busy lives.

For the first time in 20 years, the friends are finally working under the same roof; a patient with a familiar name locates Chae Song-hwa.

The hospital's medical students find inspiration in the doctors, as they look after their patients each in their own way; Lee Ik-jun receives a welcome visitor.

Yang Seok-hyeong's aloof attitude frustrates someone on his team; Jang Yun-bok and Jang Hong-do see a surprising side of Song-hwa away from the hospital.

Jang Gyeo-ul is unable to get a kind word out of Ahn Jeong-won, who seems especially cold to her; a tough professor joins the cardiothoracic department.

Kim Jun-wan waits for an answer from Lee Ik-sun, who says she needs more time; Jeong-won delivers painful news to a longtime patient's family.