ACT I
 

Sometimes this act is divided into two scenes; sometimes, as in the score, it remains undivided. In either case, the action takes place in the home of Rocco, jailer of the prison at Seville. (In the divided productions it begins inside the house and ends in the courtyard; in the undivided ones, it all takes place in the courtyard).
 

There is a one-sided romance going on between Rocco's daughter Marcellina and Rocco’s assistant,　Jacquino. The young man proposes insistently without any encouragement whatsoever from the girl, and also under considerable difficulties. Not only does Marcellina stick to her ironing, but the poor fellow is repeatedly interrupted at his wooing by summonses to open the door he is supposed to be attending. When he has finally left, Marcellina utters a sigh of relief and a very pleasant littile aria (O war ich schon mit dir vereint—"Oh, were we only married now"). Quite frankly she tells us that the man she would like to be married to is Fidelio. What she does not know is that Fidelio is a woman in disguise. She is Leonora, the wife of Florestan, a political prisoner of Pizarro's, the tyrannical Governor of the fortress of Seville. No one knows just where Florestan has been put; but Leonora, suspecting it may be right here, has disguised herself as a man, taken the name of Fidelia, and secured herself a job as first assistant to Rocco. She has been on this job for six months now without finding Florestan, but has won the devoted admiration of both her master and his daughter.
 

Roccot accompanied by Jacquino, comes in and says that he is expecting Fidelio back from the city with some new chains; and when Fidelio shows up with a particularly sturdy set, he is congratulated. An enchanting quartet is sung, in the form of a canon or rounds in which Marcellina shows that she thinks Fidelio likes her, Fidelio notes Marcellina's affections but cannot approve of them, Rocco thinks they would make a fine couple, and Jacquino fears he may be frozen out. And in simple song Rocco gives some worldly advice to the couple he believes to be virtually engaged: "He who hasn't laid up gold cannot expect a happy life."
 

In the ensuing dialogue Leonora learns of a prisoner kept so secret that no one but the jailer is allowed to visit him. She is overjoyed when Rocco tells her that, on account of the way work is getting a bit too heavy for him, she may be permitted to help. A trio follows.
 

It is at this point that many productions change from the inside to the outside of Rocco’s house, and a martial tune in the orchestra gives time for the change of scene. Pizarro enters with a troop of guards and gets his mail from Rocco. One of the letters (as he obligingly informs us by reading it aloud) is a secret warning of a surprise visitation from Don Fernando, the Prime Minister of Spain, who has heard that Pizarro has been misusing bis powers at the expense of others. He summons Rocco and orders the secret prisoner murdered forthwith but secretly, and he offers the gold-loving jailer a bribe. Rocco, accepting it, soothes his conscience by remarking that death is probably better anyway than the slow stamtion the poor fellow has been suffering on orders from Pizarro.
 

Leonora has been eavesdropping on the latter part of this scheming, and she now sings her great aria Abscheulicher! wo eilst du hin! ("O! thou monstrous fiend!'') and follows it with another one in which she expresses her hope and her faith that God and her love will yet see them through.
 

After a brief scene in which Marcellina makes it dear to Jacquino that she is not going to many him, but Fidelio, Rocco is persuaded, in the Governor's absence, to give the prisoners some fresh air—a luxury they are very seldom accorded. The wretched men, fearful of the guard on the wall, yet ecstatically happy to breathe the air of heaven, file in slowly and sing the Prisoners' Chorus, a deeply moving projection of the emotions of bewildered sufferers given a temporary taste of freedom.
 

Rocco returns from his interview with Pizarro and tells Fidelio that he has permission for him to marry Marcellina, but that now they must prepare to dig the grave of the secret prisoner. Leonora is aghast at this news and asks whether he is already dead or whether Rocco is supposed to murder him. Neither, says Rocco: Pizarro will do his own murdering; all they need do is to dig the grave^ He offers to let her off this rather dismal assignment, but Leonora insists on helping the old man even though, in her heart, she feels it must be intended for her husband, Florestan.
 

Pizarro, having heard of the unauthorized liberty accorded the prisoners, returns to denounce the jailer; but Rocco succeeds in mollifying him through a reference to the man who is about to die. The prisoners are then herded back into their cells; the doors are locked and bolted; and the act ends with soft and ominous sounds in the kettledrums.