The knight and squire remain four days as guests of Don Diego de Miranda (the gentleman in green). Don Quixote has pleasant discussions with the student son, Don Lorenzo, and is delighted to discover the boy is truly a poet. Because of the young man's virtuous and sensitive temperament, the knight all but invites Don Lorenzo to become his disciple. When it is time to depart, Sancho is sad to leave such comfortable circumstances.
Riding along once more, Don Quixote exchanges greetings with two farmers and two students. After introductions are over, the students invite the knight and squire to attend a wedding to which they are going. Comacho, the wealthy yeoman groom, is sparing no expense on the celebration. Another man also loves the beautiful bride, Quiteria. Well-favored, talented, skilled at fencing, the disappointed lover Basil is too poor to gain Quiteria's hand. The students say that Basil is so melancholy and distracted that this wedding day might prove to be the day of his death. Don Quixote declares that his sympathies go with the poor lover.
Sancho is impressed by the lavish feast prepared for the celebration. A cook casually thrusts three chickens and a couple of geese in his hands, and he immediately gorges himself on these viands while songs, dances, and a pageant are performed for the wedding guests. Discoursing together, Sancho declares to his master that he is all in favor for the bridegroom: "Comacho has filled my belly and therefore has won my heart." He strings such a long series of proverbs to prove his point that Don Quixote refrains from answering him.
When Quiteria appears, Don Quixote decides she is more lovely than anyone except Dulcinea. Suddenly Basil appears and addresses the bride.
Disheveled in appearance, distracted in attitude, he reproaches her for spurning his love and breaking her promise to him. He stabs himself with a dagger and, as a dying wish, asks the curate to marry him to Quiteria, who can then, in a few minutes, wed Comacho as an honorable widow. The bride agrees. As soon as the curate has performed the ceremony, Basil leaps briskly to his feet and embraces his new wife. Fighting begins immediately but is interrupted by Don Quixote's intervention. He concludes his speech with "those whom heaven has joined let no man put asunder," reinforcing the words with thrusts of his lance. The new bridal party leaves the scene, although Comancho holds the feast as before.
Don Quixote spends three days with the newlyweds, Basil and Quiteria. After lecturing the bridegroom to find some provident employment in order to support his beautiful wife, Don Quixote, with one of Basil's student friends as guide, departs for Montesinos Cave. The entrance to the pit is all overgrown with weeds and roots, but the knight clears the hole, ties a rope around his waist, and descends to the accompaniment of Sancho's prayers and lamentations. After half an hour, the scholar and squire pull on the rope but find no weight on it. Sancho, panic stricken, hauls in the line as fast as he can and finally feels the drag. They draw Don Quixote to the ground. He opens his eyes, as if awakening from a deep sleep. After a refreshing meal, Don Quixote proceeds to relate to them the wonders of Montesinos' Cave.