The writer František Kožík is one of the most significant Czech authors of historical novels, including the world known“The Greatest of Pierots” that has also been made into a film. At the sametime, Kožík was confronted with the dramatic history of the 20th century. In 1943, in the period of the Protectorate of Bohemia and Moravia, he travelled with a German delegation to Katyn in Poland to subsequently testify about the guilt on the part of the Soviet Union. This moment in his life was one of the reasons of his professional persecution after 1945. Moreover, one of his first post-war trips abroad in 1956 led to Hungary where dramatic events were just taking place. All of this sparked the interest of the State Security Forces,with which he agreed to cooperate. As a part of the forthcoming publication I would like to draw attention especially to the influence of the security apparatus on the life of artists in the 20th century. My main resources were documents from the Archive of the Security Forces, Museum of Czech Literature and a family archive, all of which are confronted with the memories of the writer himself. The publication is to be completed in 2014.