Mach is a Czech director and screenwriter who worked as a journalist and a theatre and film actor. In 1938, he became an assistant director on short feature films in the Grafofilm Studio, as well as Zdarfilm and Nationalfilm. Thanks to his friendship with the director Václav Kubásek, he started to work as a screenwriter. After WWII he directed his first films; at first he co-directed with Václav Kubásek the films Thunder in the Hills (V horách dun, 1946) and A Big Case (Velký prípad, 1946), and then on his own filmed the comedy Nobody Knows Anything (Nikdo nic nevi, 1947). He directed a variety of films of many different genres, such as the political drama Action B (Akce B, 1952), the comedies The Village Revolt (Vzbourení na vsi, 1951), Racek má zpozdení (1952), The Detour (Objízdka, 1968), Tri nevinni (1975), the musical comedies Florenc 13:30 (1957), Waltz for a Million (Valcík pro milión, 1961), the crime dramas Na kolejích ceká vrah (1971) and the biographies Palette of Love (Paleta lásky, 1976) about the Czech painter Josef Mánes. His most famous film in these parts is The Sons of Great Bear (Die Söhne der großen Bärin, 1966), produced by the East German studio DEFA.