Never before has private detective Tatyana Ivanova been drawn into such a stupid business - to look for a missing online friend, about whom only her online nickname is known - Moth. But Tatyana is unable to refuse her client Nikita Vasnetsov, a man, at the sight of whom her heart begins to beat to the rhythm of tango. Of course, finding Moth turned out to be a piece of cake; this could have closed the case, but the girl was recently attacked, and now she lies unconscious in the hospital. Nikita also ended up there through the fault of an unknown person, and the other day he received a letter demanding that he give up a certain treasure. Now Tatyana considers it her duty to find the attacker and find out what kind of treasure we are talking about...