Don Quixote has decided to imitate the penance suffered by his hero, Amadis of Gaul, who spent his time of distraction passively and pensively. He writes verses to his Dulcinea and does a great deal of lamenting and sighing. Sancho, meanwhile, making his way toward Toboso, encounters the curate and barber, who are stopping at the very inn where he had been tossed in a blanket. They inquire after Don Quixote, and Sancho presently tells them of all the adventures and of his present mission to Dulcinea. He now discovers that he has forgotten to take the letter, but the curate and the barber promise to rewrite it from his dictation. They remind him that in order for his master to reward his services with an earldom, he must first be made to give up "this unprofitable penance." Sancho then is willingly instructed in a stratagem to bring Don Quixote out of the wilderness.
Dressed in their disguises, that of a distressed damsel and her gentleman-usher, the barber and the curate and the squire reach the foot of the Sierra Morena. Sancho goes ahead in order to give Don Quixote the fictional message from Dulcinea, which is that he must put an end to his penance and repair immediately to her side. In the meantime, the barber and the curate meet Cardenio, who tells them the entire story of his misfortunes, Cerventes continuing the narrative at the point he left it.
Ferdinand fell in love with Lucinda and plotted to get rid of his friend in order to marry her. Sending Cardenio on a bogus errand to his brother, Ferdinand gains the father's permission to wed Lucinda, and the wedding takes place. Cardenio returns just in time to witness secretly the marriage vows of his promised bride. Saddened that Lucinda would rather marry Ferdinand than commit suicide as she promised, Cardenio plans to live his life in the wilderness, mournful and almost insane.
