Kratzert is a German director and screenwriter. He acted in theater plays during high school and then tried to enroll in film school in Potsdam-Babelsberg. He was refused because he was too young, but after serving in the military in 1960, he successfully enrolled in the department of directing. He graduated four years later and worked as an assistant director. In 1968, he made his debut with the crime drama Mord am Montag (1968). He soon got an offer from the German studio DEFA to direct films for children and became one of the most successful directors of that genre within DEFA (Wir kaufen eine Feuerwehr, 1970; Hans Röckle und der Teufel, 1974). He directed the German Western Tecumseh (1972) and the war drama Am Ende der Welt (1975). After that he devoted the rest of his career to making films for children, and the last film he made was Der Drache Daniel (1989). As the DEFA studio’s time was near its end, he began directing documentaries and videos for smaller production houses.