St. Petersburg police investigator Serdyukov, who came to Evpatoria to improve his health, is involved in the investigation into the murder of Mr. Borovitsky. He was found in a mud bath, suffocated or dead from a heart attack caused by the abundance of hot medicinal mud applied to his body. The doctor did not prescribe any procedures for Borovitsky that day. And a certain Leah Giray, a hunchback who worked there as a nurse, recently resigned from the hospital itself. Borovitsky's sister Zina assures the investigator - she recognized him as a hunchback! Only ten years ago her name was different and she didn’t have a hump!..