At a palace ball, Rigoletto mercilessly mocks the noblemen whose wives and daughters have been seduced by the Duke of Mantua—until aged Count Monterone bursts in and calls down a terrifying father's curse upon both the Duke and Rigoletto ('La maledizione!'). Shaken to the core as a father himself, Rigoletto hurries home down a dark alley, where the hired assassin Sparafucile offers his services; comparing himself to the assassin ('Pari siamo!—I stab with my tongue, he with a dagger'), Rigoletto enters his walled garden to embrace his secret daughter Gilda. Unknown to Rigoletto, the Duke has already slipped into the garden disguised as a poor student named 'Gualtier Maldè'; left alone, Gilda sings an ecstatic hymn to that fake name ('Caro nome') right as the vengeful courtiers arrive in masks to kidnap her! The next morning at the palace, the courtiers laugh over how they tricked Rigoletto into helping them kidnap his supposed 'mistress'—and inform the delighted Duke that they have brought Gilda right into the palace! The Duke rushes into his bedroom to dishonor her. Moments later Rigoletto enters, humming nonchalantly while secretly searching the room with his eyes for clues. The instant a page reveals the Duke cannot be disturbed, Rigoletto realizes Gilda is inside the Duke's bedroom! Throwing off his jester's mask, he reveals to the stunned courtiers that she is his daughter, hurling himself against the locked doors in fury ('Cortigiani, vil razza dannata') before breaking down in tears to beg for mercy. One month later, Gilda still loves the Duke despite her dishonor. To cure her of her infatuation—and execute his revenge—Rigoletto brings her at night to peer through a crack in the wall of Sparafucile's riverside tavern, where he has paid the assassin 20 scudi to murder the Duke. Disguised as a cavalry officer, the Duke arrives asking for wine and a room, brazenly singing that women are fickle ('La donna è mobile'). In the famous Quartet ('Bella figlia dell'amore'), the Duke seduces Sparafucile's sister Maddalena inside while Gilda weeps outside and Rigoletto vows vengeance. Smitten with the handsome stranger, Maddalena begs her brother to spare him; Sparafucile agrees that if another traveler knocks before midnight, he will kill the substitute instead. Overhearing this, Gilda puts on riding clothes, knocks at the tavern door in the lightning storm, and takes the blade meant for the Duke. At midnight, Rigoletto receives the body in a sack—only to hear the Duke singing 'La donna è mobile' alive in the distance! Tearing open the sack, he finds his dying daughter Gilda and screams: 'Ah, the curse!'