At the request of Duma deputy Fyodor Khovansky, a detective from the agency “Unfaithful Spouses” Gosha Ladushkin relentlessly monitors his wife’s every move. After some time, Inara Khovanskaya flies to Cologne, and the detective follows. And not in vain: he sees Inara entering the brothel. And a few days later Gosha learns that Khovansky, poisoned by an unknown poison, suddenly dies in his office. Deciding to take revenge, the widow accuses Ladushkin of her husband’s death, but he has no alibi... Private detective Anna Svetlova decides to help her friend: the widow is very determined and will do anything to deal with the annoying detective...