Slovak serial. Two siblings spend their summer holidays at grandparents in the castle Bojnica. Lesson about classical musical instruments in the form of detective story.
Also Slovak movie, I mean the film language is Slovak. In former Czechoslovakia were basically two main film factories, one in Prague (Barrandov), producing mainly Czech movies, and another in Bratislava (Koliba), producing mainly Slovak movies. Except of those two there was a film factory in Gottwaldov (today Zlín), producing mainly child movies, and also ateliers of animated cartoons.