Sarastro finds the desperate Pamina and consoles her, explaining that he is not interested in vengeance. Tamino and Papageno are told by a priest that they must remain silent and are not allowed to eat, a vow that Papageno immediately breaks when he takes a glass of water from a flirtatious old lady.
When he asks her name, the old lady vanishes. Tamino remains silent even when Pamina appears. Misunderstanding his vow for coldness, she is heartbroken.
The priests inform Tamino that he has only two more trials to complete his initiation. Papageno, who has given up on entering the brotherhood, longs for a wife instead. He eventually settles for the old lady. When he promises to be faithful she turns into a beautiful young Papagena but immediately disappears.
Pamina and Tamino are reunited and face the ordeals of water and fire together, protected by the magic flute.
Papageno tries to hang himself on a tree but is saved by the three spirits, who remind him that if he uses his magic bells he will find true happiness. When he plays the bells, Papagena appears and the two start making family plans.
The Queen of the Night, her three ladies, and Monostatos attack the temple but are defeated and banished. Sarastro blesses Pamina and Tamino as all join in hailing the triumph of courage, virtue, and wisdom.