Shiho was a neurological surgeon who decided to resign after hallucinating during an operation. But the director of the Toko University Hospital, held Shiho in high regard, and invited her to the Analysis and Diagnostics Department as a diagnostician, to identify and determine the etiology of diseases that doctors have not been able to explain. Shiho has an upright personality and a strong sense of justice, with an even strong desire to save patients. This sometimes causes her to flare up. She joins the all-female motley crew of physicians in the Analysis and Diagnostics Department, working together and occasionally bumping heads, to solve the mystery of the unexplained diseases.