May 25, 2021
After being interned and tortured at Pankrác prison for two years (1943–1945) Karel was sent to Theresienstadt prison. The conditions in the prison were dire and he became ill with dysentery and pneumonia. SS-Oberscharführer Stefan Rojko sent all ill prisoners outside in freezing cold to disinfect the cell. As a result Karel and 8 other prisoners died on 6 March 1945.
In Pankrác and Theresienstadt he continued working. He composed five-act fairy-tale opera Three Hairs of the Wise Old Man, writing on toilet paper using pencil or medicinal charcoal. The 240 sheets containing a detailed sketch of the opera was secretly passed to a friendly warden. The orchestrations were completed after his death and from his notes by his pupil Zbynek Vostřák.