Jan Tříska
Jan Svozil
Jana Hlaváčková
Vlasta Martínková
Gabriela Wilhelmová
Hana
Zdena Herfortová
Eva Svozilová
Oldřich Vykypěl
ROH chairman
Vilém Pfeiffer
Bartoněk (uncredited)
Milan Pásek
Institute director (uncredited)
Miroslav Donutil
Assistant (uncredited)
Zdeněk Maryška
Assistant (uncredited)
Jana Gazdíková
Secretary (uncredited)
Jana Hliňáková
Jaroslav Rava
Stanislav Hradecký
Oldřich Slavík
Jaroslav Stehlík (uncredited)
Jiří Hanák
Miroslav Janoušek (uncredited)
Jiří Dušek
Zdražil (uncredited)
Karel Adam
Department manager (uncredited)
Helena Trýbová
Scientist (uncredited)
Vladimír Pavlar
Doc. Rozehnal (uncredited)
Bohumil Slezáček
Professor (uncredited)
Arnošt Navrátil
Doctor (uncredited)
Sylvie Nitrová
Nurse (uncredited)
Marcela Dürrová
Laboratory assistant (uncredited)
Milan Kročil
Assistant (uncredited)
Zdeněk Dryšl
Houseman (uncredited)
Blažena Rýznarová
Official (uncredited)
Markéta Rauschgoldová
Canteen assistant (uncredited)