Mister Iks

Mister Iks () is a Russian musical comedy film directed by . It is based on the Leningrad Theatre of Musical Comedy operetta of the same name from 1956. The operetta itself was a Russian adaptation of Emmerich Kálmán's "Die Zirkusprinzessin".
Filming began in 1957, with many of the actors and artists from the Leningrad Theatre working on the film. It premiered in the Soviet Union and other countries on May 2, 1958.
Plot.
A mysterious man under the name Mister Iks performs in the circle, playing violin, on a chair suspended in the air by ropes. His breathtakingly sad melodies reflect his internal turmoil – his love with a noble woman and the fact his relationship is frowned upon by society. A beautiful story of friendship, love, and circus are accompanied by the voices of the actors.
Although the music is from Kálmán's operetta, the setting was changed from Tsarist Russia to France.
Changes from the operetta.
Although the film was based on Emmerich Kálmán's "Die Zirkusprinzessin," which had premiered at Theater an der Wien in Vienna on 26 March 1926, significant changes had to be made because the operetta was set in Tsarist Russia and as such had many themes which were unacceptable to the censors. The film was moved from Saint Petersburg to Paris, the characters became French, and the Hussar's aria of Mister Iks was replaced by a marine aria. The actor who played Pelican wrote:
No other Kalman's operetta made in the Soviet Union had as many different variants as "The Circus Princess", and when it had the first appearance in the Soviet Union, the operetta had one embodiment in Moscow, and another one in Leningrad. Therefore, the first comic of the theatrical troupe in Moscow portrayed the Grand Duke Nicholas Nikolaevich of Russia during his exile in Paris. Instead of the troupe a rich American appeared in Leningrad theatre, where Pelican was portrayed as a waiter working at a restaurant while at the same time as a White Russian General; emigres disappeared from further variants of this operetta.