Otakar Vávra's film Kladivo na čarodějnice (Malleus Maleficarum, also translated as Witches' Hammer or Witchhammer, 1969) is based on Václav Kaplický’s book Kladivo na čarodějnice (1963), a novel about witch trials in Northern Moravia during the 1670s.
His novel Kladivo na čarodějnice (1963), about witch trials in northern Moravia during the 1670s is the best known because it served as the basis for movie by Otakar Vávra (Malleus Maleficarum, also translated as Witches' Hammer or Witchhammer).