Zaira, a Christian captive, is to marry Sultan Orosmane. Her father Lusignano is also imprisoned and recognises her as his daughter, distressed that she has become a Moslem. Orosmane is jealous of the Christian knight Nerestano, who is, in fact, Zaira's brother, and after various complexities in the plot, kills Zaira. When he learns the truth, he kills himself.
Zaira won no success and Bellini later made use of parts of it for other works, designed for theatres of greater importance.