Golden blood. Damn flail

Apparently, a serial killer has appeared in Moscow: a second dead body with a letter painted on its forehead has already been found, and no connection between the victims has been found. However, Vadim and Svetlana believe that the choice of the killer fell on these people not by chance. Vadim finds out that the second victim was secretly communicating with someone on the phone, and when this mysterious subscriber is detained, he notices an equally mysterious imprint on the ground. This is a trace of a very rare and ancient coin. The heroes gradually unravel the tangle of secrets, but do not approach the killer. And gradually there is a feeling that it is not they who are following his trail, but he is chasing them.