Composer Petr Hapka has stated that he considered the music for this piece to be his finest work for film.
Some of the sets and costumes were also used in another film by Juraj Herz, La Belle et la Bête (1978) (which he filmed simultaneously), and parts of the sets also in Le Prince des chats (1979) and Tajemství Ocelového mesta (1979).
Actor Frantisek Filipovský, who played the court jester, coincidentally also played the court jester in another fairy tale in the same year, Princ a Vecernice (1979).
In Josef Hanzlík's original script before his collaboration with Juraj Herz, the main villain was not an astrologer and hypnotist, but a "black knight". This was also the title given to the first version of the script.
Juraj Herz later returned to this material and, together with Jan Drbohlav, adapted it as a stage play of the same title. It was performed in 2011-2013 at the National Theatre in Prague, again under the direction of Juraj Herz.