The segment from a Degl film production company newsreel captures the 50th anniversary celebrations of laying of the cornerstone of the National Theatre. The celebrations took place on 16-18 May 1918 in Prague, with the participation of representatives of all Slavic nations of the Austro-Hungarian Empire. The first shots show the festively decorated building of the National Theatre. In the next part, the camera observes the events taking place in the upper part of Wenceslas Square. The staircase and the ramp of the National Museum, where the opening ceremony took place (specifically in its Pantheon), are filled with young people in national folk costumes. Shots of the crowded square. Cultural and political figures, such as poets Adolf Heyduk and Pavol Országh Hviezdoslav, writer Alois Jirásek and the head of the National Theatre Opera Karel Kovařovic, are leaving the building of the National Museum. This is followed by the symbolic ceremonial removal of politician Karel Kramář from the building. Afterwards, the Slovenian writer and mayor of Ljubljana Ivan Tavčar is seen leaving the building, as well as Czech actors Eduard Vojan, Marie Hübnerová, Leopolda Dostalová, Marie Laudová-Hořicová, Karel Želenský, writers Ignát Herrmann, František Herites and Jan Herben with his wife Bronislava, poet Bohdan Kaminský, politicians Alois Rašín, František Soukup, Gustav Habrman, Václav Klofáč and other notable national figures.