Ubaldo Piangi is a minor character and the male counterpart of La Carlotta. He is the leading male in most all of their productions. In the film version, he appears to be romantically involved with Carlotta.
When Piangi plays the part of Don Juan in the Phantom's opera, the Phantom strangles him behind stage and takes his place for the song "The Point of No Return", directly after which he kidnaps Christine.
Actors such as Wynne Evans (who played the part in the 25 year anniversary of the Phantom of the Opera in the Royal Albert Hall) and Zachary Ghazi-Torbati (who portrayed the part in the schools UK premier) have played the role of Piangi.