In the L'Homme au complet marron episode of TV series Les Petits Meurtres d'Agatha Christie, Sergueï Pochenko is the brother of the famous Russian ballerina Tatiana Pochenko.
The brother and sister pair are unwilling operatives of Russian intelligence, forced to work for them only because the authorities in Moscow threaten to take reprisals against their mother if they do not. During the events in the episode, Tatiana is performing as a guest artiste at the Lille Opera. They are given some microfilms to courier back to Moscow. However Tatiana hides the microfilms away and the two of them hope to defect to the French authorities. They reason that as long as they hold the microfilms, Russian intelligence would not take action against their mother and they can negotiate for her release. The main threat to the brother and sister pair is "The Colonel", a Russian masterspy who suspects they are trying to defect and are trying to retrieve the microfilms. A major effort on Sergueï's part is trying to discover the real identity of "The Colonel".
Sergueï Pochenko is "the man in the brown suit" in this adaptation and he is seen at various junctures. He is a witness when Nadine Mercuret is shot and also when Jules Touchard is run down (the nearest parallel to the accident which befalls L. B. Carton in the original. Here Sergueï does not go up to the body and pretend to be a doctor). However Sergueï Pochenko cannot really be considered a parallel of Harry Rayburn who is the man in the brown suit in the original.
Sergueï Pochenko is portrayed by Anton Yakovlev.