Záhada hlavolamu

In the spring of 1967, the director Hynek Bočan came up with the idea to make a feature film based on the novels Záhada hlavolamu and Stínadla se bouří, who, after the approval of their author Jaroslav Foglar, started writing the script together with Václav Šašek. They offered it to the Barrandov Film Studio and the Gottwaldov Film Studio, but neither was interested in the project. On the contrary, it was shown by Czechoslovak Television, whose dramaturgs decided that it would be a seven-part series. Therefore, the authors edited the script in cooperation with dramaturg Josef Bouček. Part of the introduction of the first part were also some scenes that have their origins in the comics about the Rychlé šípy.^[4] For the roles of individual Fast Arrows, Bočan was looking for boys who would typically correspond to Jan Fischer's comic portrayal of these characters. Jiří Lukeš was eventually chosen from several hundred applicants for the role of Mirko Dušín, Tomáš Hádl was to portray Jarka Metelka, Roman Skamene won the role of Červenáček and Zdeněk Jánský was cast as Jindra Hojer. All four of them already had some experience with filming. The representative of the last missing role, Rychlonožka, was found in Martin Kapoun, for whom it was the first and only film work. Other characters were portrayed by actors Jaromír Hanzlík, Ivan Vyskočil and others.

In December 1968, a five-day training camp was held in the Krkonoše Mountains, which was intended for the representatives of Rychlé šípy to get to know each other. Filming of the series, produced by the Czechoslovak Television's Television Film Production, began in December 1968 and lasted until the beginning of summer 1969. It was filmed in the studios in Prague in Barrandov, where the decoration of the entire city quarter – Stínadel – was built. The crew also used studios in Prague's Hostivař and also some exteriors in Prague.^[5] During filming, it was decided in March 1969 that nine episodes would be produced instead of seven. The mystery of the puzzle became the first Czechoslovak television series intended for young people.

The music for the series was composed by Jiří Šust and recorded by the Film Symphony Orchestra under the direction of Štěpán Koníček.

• Website (in Czech)
• IMDb.com