It opens with a duet between Jacquino and Marcellina, and also features Rocco, Don Fernando, and Pizarro, who is the governor of the prison where it takes place.  
The first act features a canon sung by four characters, "How wondrous the emotion," after which the tone becomes more earthy with the aria which opines that life is nothing without money.  The second act features the duet "Joy inexpressible," after which a minister of state recognizes a man whom he thought was dead.  It is based on a play by Jean Bouilly, and earlier musical versions of it had been written by Pierre Gaveaux and Donizetti's teacher, Simone Mayr.  It opens with a duet between Jacquino and Marcellina, and also features Rocco, Don Fernando, and Pizarro, who is the governor of the prison where it takes place.  FTP, name this work which premiered in 1806, an opera about a Spanish noble named Florestan and his wife Leonora which was written by Ludwig van Beethoven.
The first act features a canon sung by four characters, "How wondrous the emotion," after which the tone becomes more earthy with the aria which opines that life is nothing without money.  
Fidelio