Lancelot is unable to act on his love for Guenever because his religion and Arthur’s own principles about fairness and justice, in which Lancelot believes deeply, forbid him to do so. While everyone else thinks Lancelot is a great man, he hates himself.
Lancelot stays at Arthur’s court in Camelot for several weeks, but he cannot bring himself to do anything about Guenever. He is afraid that if he sleeps with her, he will lose his strength and his position as Arthur’s best knight. Uncle Dap advises him to go on another quest, so he makes his way to the haunted castle of Corbin, which is owned by King Pelles. On the way, Lancelot is stopped by villagers who tell him that fairies, among them Morgan le Fay, have put a spell on a local girl and placed her in a vat of boiling water, from which she can be saved only by the best knight in the world. Lancelot tries to refuse, but they insist, and he ends up pulling a naked young woman named Elaine out of the vat. Afterward, they are greeted by Elaine’s father, who turns out to be King Pelles. Pelles invites Lancelot to stay. Excited by Elaine’s great beauty, Lancelot cannot yet understand that he has performed a miracle.
At the castle of Corbin, Lancelot is miserable and thinks of Guenever. Pelles’s butler cheers Lancelot with wine. While Lancelot is intoxicated, Pelles’s butler tells Lancelot that Guenever is staying at a nearby castle, waiting for Lancelot. Lancelot rushes off to see her. The next morning, he wakes up and sees that the woman in bed with him is Elaine. Realizing that he has been tricked, Lancelot threatens to kills Elaine. He thinks that his strength lies in his virginity and that he will now no longer be able to work miracles or be the best knight. Elaine tells Lancelot that she loves him and wishes to bear his child, whom she will name Galahad. Lancelot says that since she tricked him the baby will be hers alone and that he is leaving.
At Camelot, Guenever thinks of Lancelot as she stitches a new shield cover for Arthur. Convinced that Elaine has ruined him, Lancelot sees no point in not furthering his destruction, and he races up the stairs to Guenever. Before they realize what is happening, they have slept together.
King Ban, Lancelot’s father, is under attack and writes Arthur to ask for help. Arthur leaves for France after asking Lancelot to stay behind and guard his kingdom. While Arthur is away, Lancelot and Guenever spend twelve happy months together. Lancelot tells Guenever that when he was little, he was a very holy little boy, always punishing himself for the slightest faults. Lancelot tells Guenever that he originally stayed away from her because he was worried that by sleeping with her he would lose his ability to perform miracles. He adds that he is giving her his God-given gifts as a present for her love, and that he does not regret it.
When Guenever learns, however, that Elaine has given birth to a baby boy named Galahad—Lancelot’s first name—she realizes that Lancelot and Elaine have slept together. Hurt, Guenever becomes petulant, lashing out at Lancelot and threatening to have Elaine executed. Eventually, Lancelot and Guenever are tearfully reconciled, but a seed of hatred and distrust has been planted in their love affair.