Mister X
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, "" (Two fairy-tale eyes), has been recorded by several famous tenors, including Fritz Wunderlich, Charles Kullman, and Richard Tauber.