Echegaray pokes gentle fun at the grandiloquence of Italian opera, singers and entrepreneurs, though his back-stage action centres on a performance of a famous French opera of the time - Meyerbeer's L'Africaine (1865), which portrays a romantic liaison between Vasco da Gama and an African girl, Selika. The climax of the farcical action is an avatar of the Marx Brothers' film A Night at the Opera, with relatives and police invading the stage during a performance of the Love Duet from Act 4 of Meyerbeer's opera.
Caballero's music may quote the theme of Meyerbeer's Duet and use Italianate forms, but he always retains his distinctive, tuneful elegance and subtle humour. The Jota for the tenor and soprano, in particular, remains one of the staple favourites of the zarzuela repertoire. Caballero's sequel to El dúo de La Africana, entitled Los Africanistas (1894) did not enjoy much success and has never been revived.
Scene 1 - The rehearsal room of a theatre. After a gentle Preludio, partly based on the theme of Meyerbeer's duet, Pérez, the stage manager, greets the chorus for the morning rehearsal. They are a lively lot, full of gossip and flirtatious banter and he has difficulty getting them settled down ready for a rehearsal of La africana, which they are to perform that evening (Coro: "Buenos días, Inocente").
The Italian impresario, Querubini, greets Pérez. In an amusing mixture of Italian and imperfect Spanish, he berates the harassed stage manager for wasting time rehearsing, when they haven't as yet even sorted out scenery and costumes for the evening. He feels that the set available from La Gran Vía is somehow not quite right, but is unwilling to engage a painter to convert the gardens of the Madrid Retiro into an African jungle. Left alone, the impresario indulges in a verse soliloquy to the audience. His chief concern is money. Fortunately his new wife, Antonia La Antonelli, is prima donna of the company, and his daughter Amina is the leading mezzo, so he doesn't have to pay them. What's better, the new tenor Giussepini, though possessed of a magnificent voice, doesn't want paying at all, but sings for love of art. All of which makes for a cheap company and a healthy bank balance.
Amina, who dislikes her stepmother intensely, tells her father the truth - Giussepini is not singing for love of art but rather for love of La Antonelli. No sooner has Querubini gone to his office to ponder his situation, than the tenor comes in with the ladies' chorus to rehearse. They are joined by La Antonelli with the men. The two principals talk about their favourite opera roles and indulge in light banter. Giussepini praises the women of Seville - which happens to be Antonia's birthplace - whilst she is loud in favour of the lusty men of Aragón, the tenor's homeland (Coro y solos: "Amigas mías y compañeros").
Querubini storms in, querulously berating the company for wasting time when they should be rehearsing. He is subdued by his masterful wife, and they begin to rehearse the Act 4 Duet. Amina directs her father's attention to the way in which Giussepini is passionately overstepping the mark, and Querubini jealously interferes, Giussepini complains that he is interfering with his art. The impresario drags his wife away, and the tenor leaves with a flourish from Rigoletto - "La donna é mobile" (Melodrama: "Oh mía Selika").
The chorus has thoroughly enjoyed the offstage drama, and comments on the situation with quiet glee (Coro de la murmuración: "Se marcha furioso"), a delicious number which echoes the chorus "Saria possibile?" from Donizetti's L'Elisir d'Amore.
Scene 2 - Querubini's office, before the evening performance. The company's Bass singer is pursuing Amina, but she mocks his basso profondo ardour and teases him into a frenzy. Querubini comes in to investigate the disturbance, and complains that Amina is as frail as her mother, a Neapolitana who ran off with a policeman. A perfect solution suggests itself - he will offer his daughter's hand to Giussepini, thus safeguarding wife and daughter at a stroke. Under a thin veneer of friendship he makes his offer, but the tenor will have none of it, claiming his vocal powers will diminish with the duties of matrimony. In a witty duet the surface politeness of the two men is contrasted with the jealousy and scorn that lie beneath (Dúo: "Casa mia figlia").
Scene 3 - Backstage in the wings of the theatre, during the 4th Act of La africana. The stage is visible, and Giussepini has reached the infamous phrase "Oh, mia Selika!". Carried away by the emotion of the moment, his hands begin to stray. Querubini cannot restrain his jealousy. He runs onto the stage to try to murder the tenor, but Pérez quickly brings down the curtain and the chorus separate the combatants. A Police Inspector has been called, and as he vainly attempts to ascertain the facts of the situation, Pérez takes the opportunity to get the two singers out on stage again.