Afanasy Karachaev was found dead in his apartment. The official conclusion of death indicates heart failure, but Lyalya, who loved Karachaev, does not believe this conclusion. She turns to private detective Alexei Kisanov, who takes up the case. Very soon it becomes clear that Karachaev was helped to go to the next world. But this was the first and last clear point in this matter: what follows is complete riddles. The daughter of Afanasy Karachaev disappears in the most mysterious way, and a detective is looking for her traces in the dark waters of the Moscow Sea. Versions multiply like molecules in organic chemistry. Inheritance? Business interests? Revenge of a jilted lover? Alexey Kisanov has never had such a murky case before! The solution will only appear at the very end...