Jung Yoojin, a psychologist, landed herself a job in a mental asylum that specialises in the treatment of severe mental illness such as schizophrenia, bipolar disorders and depression. Her first task was to help Baek Yebin, a patient who was admitted to the hospital for severe schizophrenia and bipolar disorder. However, as Yoojin continued to hold consecutive sessions talking to her, she found herself falling deeper and deeper for the girl.