Istanbul at the end of the 19th century. A city where splendor coexists with poverty, and the traditions of Europe with the traditions of Asia. This city is accustomed to cruel and mysterious crimes. But this time the incredible happened. The waves of the Bosphorus brought the body of a young Englishwoman to the shore. Who killed her? And why was everything torn off the body of the deceased except the pendant with the seal of the deposed sultan? The famous “kadi” - the judge and investigator Kamil Pasha - is required to find the criminals as soon as possible. But so far his only clue is the very dubious testimony of the daughter of the British ambassador, who claims that the dead girl is already the second victim of the mysterious killer...