Catarina and Rebolledo accept the proffered hospitality, but the latter quietly makes his exit when Diana begins to read an account of a robbery which contains a description of himself and his companion.  Catarina remains, however, in spite of Don Henrique’s warning that she is in the house of the Minister of Police.  In a moment of passion he declares his love for her and begs her to fly with him.  She declines his proffer, but gives him a ring as a souvenir.  A pretty little duet ("If I could but Courage feel”) ensues between Diana and Don Henrique, in which she gently taunts him with his inattention to her and his sudden interest in the handsome stranger.  At this juncture the Count enters in wild excitement over the announcement that the crown jewels have been stolen.  Don Henrique’s ring is recognized as one of them, and in the excitement which ensues, Catarina finds herself in danger of discovery, from which she is rescued by Diana, who promises Don Henrique she will send her away in the Count’s carriage if he will agree to refuse to sign the marriage contract.  He consents, and she departs upon her errand.  At this point in the scene Don Henrique sings the beautiful ballad, “Oh, whisper what thou feelest!” originally written for Mr. Harrison.  This song leads up to a stirring finale, in which Don Henrique refuses to sign the contract and Catarina makes her escape.

The last act opens in the anteroom of the royal palace at Lisbon, where Diana is waiting for an audience with the Queen.  She sings another interpolated air, originally written for Louisa Pyne ("When Doubt the tortured Frame is rending"), and at its close the Count, Don Henrique, and Don Sebastian enter.  While they are conversing, Rebolledo appears, announced as the Count Fuentes, and a quintet occurs, very slightly constructed, but full of humor.  An usher interrupts it by announcing the Queen will have a private audience with the Count Fuentes.  While awaiting her, the latter, in a monologue, lets us into the secret that the real crown jewels have been pledged for the national debt, and that he has been employed to make duplicates of them to be worn on state occasions until the real ones can be redeemed.  The Queen enters, and expresses her satisfaction with the work, and promotes him to the position of Minister of Secret Police.  On his departure she sings a charming cavatina ("Love, dwell with me"), and at its close Count de Campo Mayor enters with the decision of the Council that she shall wed the Prince of Spain.  She returns answer that she shall make her own choice.  The Count seeks to argue with her, when she threatens to confiscate his estate for allowing the crown jewels to be stolen, and commands him to arrest his daughter and nephew for harboring the thieves.  Diana suddenly enters, and an amusing trio ensues, the Queen standing with her back to Diana lest she may be discovered.  The latter fails to recognize her as Catarina, and implores pardon for assisting in her escape.  The