This article examines several aspects of the theme of the theatre that are significant to the works of the renowned playwright А. N. Ostrovsky as well as the “glorifier of the Urals” D. N. Mamin-Sibiryak. The resemblance to Ostrovsky in Mamin’s play The Gold Prospectors (At the Golden Bottom) (1887–1888) is evident at the level of material and subject matter. Both Mamin’s gold finder Molokov and Ostrovsky’s merchant Bolshov (It’s a Family Affair — We’ll Settle It Ourselves) experience a similar background of deliberate bankruptcy and subsequent failure. The article devotes particular attention to the unexpected resemblance between The Gold Prospectors and Ostrovsky’s historical drama, Vasilisa Melentyeva, which was written with the participation of S. A. Gedeonov. The vividly dramatic part of Vasilisa Melentyeva was one of M. M. Abramova’s (née Heinrich), Mamin’s second wife’s, favorite roles, and her husband considered it to be her best role. The concept of the impenitent sin (N. Shalimova) was a recurring theme in the works of both Ostrovsky and Mamin. In contrast with Ostrovsky’s drama, Mamin’s social and domestic drama comedy presents a secret relationship between reasons and consequences, guilt and punishment. The ultimate outcome of the dramatic work evinces that the infliction of moral punishment has an impact on all the characters, thereby endowing the play with an apologue-like quality. The second aspect of the theatre theme in the article is an examination of the interrelation of the theatre and the public in Mamin’s stories of the mid-1880s (We Need to Encourage Art, Buyanka) and Ostrovsky’s plays, mainly his comedy Talents and Admirers. Ostrovsky differentiates the public taking into account who appeals to it: “respectable people” — or actors themselves and the entrepreneur, who often has to speak the language of money, but never forgets about the theatre’s truth. In Mamin’s narratives, the public is represented as a collective entity, symbolising the mundane and consumerist aspects of modernity. However, they are also depicted as educated provincial individuals who possess a genuine passion for the performing arts. A discernible correlation is established between Mamin’s characters and Ostrovsky’s own statements regarding the theatre and the public. This correlation is identified through an examination of Ostrovsky’s notes on the position of the theatre and dramatic art in Russia.