The theater auditorium is decorated with a curtain by Henryk Siemiradzki, a Polish historical painter. This curtain was unveiled a few months after the ceremonial opening of the theater, on April 18, 1894. It is a painting on canvas, over 11 meters wide and almost 10 meters high, separating the stage from the audience.
The painting is allegorical in nature, and the painted figures are shown against the background of ancient architecture.