Die Zirkusprinzessin

Die Zirkusprinzessin (The Circus Princess) is an operetta in three acts by Hungarian composer Emmerich Kálmán to a German libretto by Julius Brammer and Alfred Grünwald. It premiered at the Theater an der Wien in Vienna on 26 March 1926 and went on to 344 performances there.
The plot revolves around a romantic intrigue with interpolated circus sequences. The mysterious "Mister X", a dashing circus performer, is hired by a disappointed suitor of Princess Fedora Palinska to pose as a nobleman and marry her. "Mister X" is in fact a nobleman, the disinherited nephew of a deceased prince. One of the work's most well-known arias, Zwei Märchenaugen (Two fairy-tale eyes), has been recorded by several famous tenors, including Fritz Wunderlich, Charles Kullman, and Richard Tauber.