Eijiro Saito graduated from the prestigious Eiroku University Medical Department and started his residency at Eiroku University Hospital. Eijiro's first internship is in Surgery Department 1, and his supervisor is Takahisa Shiratori, who is said to be a talented surgeon. Eijiro is training with Kuniya Dekune and Masaomi Munakata. However, the reality of the internship is that he is a page boy, working an average of sixteen hours a day for 38,000 yen a month! He has to earn his living by working part-time as a duty worker at another hospital. Eijiro chooses Seido Hospital, where Osamu Hattori is the director. The operating room, which accepts emergency patients from traffic accidents, is a veritable battlefield. There, he is shocked by the work of doctors Katsuo Ushida and Kaori Akagi.

Eijiro, a resident in Surgery Department 1 at Eiroku University Hospital, is assigned by his supervisor Shiratori to take care of an elderly man named Kaneko, who is in a coma. This is Eijiro's first patient, and he is filled with anxiety. However, he remembers what Hattori, the director of Seido Hospital, told him: never run away from a patient again. This renews his determination as a doctor. Eijiro is eager to treat Kaneko, but is told by Shiratori that there is no need to give Kaneko life-prolonging treatment. One day, Kaneko's condition suddenly changes. Eijiro desperately tries to take steps to save him, but despite this, Shiratori announces to Kaneko's daughter, Akiko, that the life-prolonging treatment will be discontinued. After that, Akiko stops coming to visit him.

Eijiro's next training site is Internal Medicine Department 2, commonly known as Cardiology. He observes various examinations with fellow resident Dekune, but along the way, they encounter a situation that requires an emergency operation by the cardiac surgeon. Eijiro and Dekune go to the cardiac surgeon's office to request the operation. The patient, Kazuo Miyamura, has unstable angina and needs surgery right away. Eijiro demands that the surgery be performed as soon as possible at a conference with the cardiac surgery department but is told that the schedule for the surgery will be decided by the cardiac surgery department. Eijiro has doubts about the medical office system but cannot do anything about it and lies to his patient for the first time.

Eijiro meets with Saburo Kita, a professional cardiac surgeon introduced to him by Kaori, with the fervent intention of helping Miyamura, a patient in his care who needs a highly difficult operation. Kita understands Eijiro’s behavior but says he cannot perform the surgery. Meanwhile, rumors circulate in the hospital that Eijiro has been picking a fight with Professor Fujii, a cardiac surgeon, and his position deteriorates. It is officially decided that Miyamura will be transferred to the surgical ward, and Eijiro tries to help Miyamura somehow by calling cardiac surgeons around the country in search of a doctor who will perform the operation. Meanwhile, Eijiro’s mother, Tomoko, comes to Tokyo. Touched by her deep love for him, Eijiro’s mother's words help him come to a certain decision.

Kita decides to take on the heart surgery of Miyamura, who has been voluntarily discharged from Eiroku University Hospital. However, it is a highly difficult operation, and the surgeon will be Kita's number one student, Ichiro Tori. Kita says he still cannot hold the scalpel. Miyamura is admitted to Fuchinan Memorial Hospital and is introduced to Tori, but he most wants to meet Kita. However, Kita continues to refuse. Eijiro returns to Eiroku University, where his position is further strained by his defiance against Professor Fujii. His part-time job at Seido Hospital to earn living expenses comes to an end due to pressure from the university. His work at Internal Medicine Department 1 has also dried up, and the next place of internship refuses to accept him and harasses him.

Eijiro's next training assignment is in a neonatal intensive care unit (NICU). On his first day, Eijiro's supervisor Takasago sarcastically and harshly criticizes him, but nurse Minagawa welcomes him, saying that they are short-staffed. One night, Yoshiko Tanabe is brought in. She is twenty-eight weeks pregnant, her water breaks, and it’s decided she needs an emergency C-section operation. The children born are twins, an older brother weighing 870 grams and a younger brother weighing 850 grams. The twins are intubated and require respiratory management, and it would not be unusual if they suffer a pulmonary hemorrhage. Eijiro and Takasago take care of the twins, but Takasago notices something unusual. At night, the father, Hidekatsu, arrives at the hospital.