Слишком много любовников

A certain Vyacheslav Dvubratov addressed me, private detective Pavel Sinichkin, giving the impression of a provincial bandit. He asked to find his missing mistress Alena and immediately issued an extremely generous advance. Alena worked as a manicurist, lived with her unlucky husband in a one-room apartment, they had no children - it would seem that there was nothing to catch on! To begin with, I went to talk to Alena's husband, but found him dead. Nothing to say, good start! I decided to abandon this dubious business, went to the hotel to Dvubratov to return the advance, but I found him dead in my own room ... What was the modest manicurist hiding if her disappearance led to such strange and terrible events?