Recently transferred to the Department of Mental Health, Jeong Da-eun's first patient is Oh Ri-na - a woman who appears to be perfectly fine.

Da-eun overhears the hard truth and is hurt by it. As tensions come to a head, doctors and nurses settle their disagreements the old-fashioned way.

Trainee nurses visit the psychiatric ward, but one of them displays strange behavior. Da-eun accidentally learns a secret about her bestie, Song Yu-chan.

A hostile patient accuses Da-eun of stealing money. Meanwhile, Min Deul-re offers Hwang Yeo-hwan a glimpse into her life to show him her reality.

During an emergency, Da-eun sees another side of Dr. Dong Go-yun. Senior nurse Park Soo-yeon relates to a patient juggling motherhood and work.

Facing monetary issues, Deul-re distances herself from Yeo-hwan. Da-eun grows concerned about a discharged patient reintegrating into his daily life.

Da-eun's friends and colleagues worry for her after a tragedy while the doctors, nurses and patients learn about treating PTSD.

Finding it hard to heal without slowing down, Da-eun tries to face her emotions. Yeo-hwan and Go-yun commiserate over their relationship issues.

Deul-re deals with her mother's return. Da-eun finds herself in her patients' shoes as she grapples with her own diagnosis.

Da-eun learns how to prioritize herself, but faces fears of returning to work - until she receives empathetic words of courage from the head nurse.

Now the subject of office gossip, Da-eun returns to work. During a night out with friends, Deul-re rediscovers what makes her happy.

Da-eun manages to find a unique way to help her patient. Deul-re pursues her passion and Yu-chan takes a bold stand.