“Secrets of Great Ukrainians. Danylo Halytsky” is a documentary film. Danylo Halytsky or Daniel of Galicia (1201-1264) was a King of Ruthenia (Rus'), Prince (Kniaz) of Galicia (Halych). The era of Danylo Halytsky is one of the most mysterious periods of Ukrainian history. Scientists still cannot find his golden crown. His royal castle, which withstood two Mongol invasions, also disappeared from all maps. The authors of the film will try to present a graphic reconstruction of king castle.