All of the great families that feature in this story have a sort of genius or tutor in the family: Arthur had Merlyn, Gawaine and his brothers had Sir Toirdealbhach, while Lancelot has Gwenbors or Uncle Daps. Uncle Daps is Lancelot's uncle and very well learned in chivalry and armor. He also used to be the best swordsman in France—for this reason primarily Lancelot had become attached to him.
Although White compares Uncle Dap to Merlyn, he is in no way comparable—Uncle Daps is neither wise nor eccentric, nor does he seek to challenge Lancelot. He is simply incredibly faithful and resilient.
One day in late Summer, Uncle Daps and Lancelot are practicing in the Armory. A page comes in to say there are visitors for Lancelot. Entering his mother's chamber, Lancelot encounters an elderly gentleman with a white beard and a young woman with an olive complexion. Merlyn (the old man) announces to Lancelot that he will be the finest knight Arthur ever has, and that Arthur and Guenever send their love. Lancelot asks if Arthur has chosen all of his knights—Merlyn looks confused and shifty. He says Arthur has twenty-one still to chose. With this, Merlyn and his new wife Nimue must depart for their honeymoon and vanish. Lancelot hurries off to find Uncle Dap and announces that he is going to England, but that Uncle Dap must not tell his parents.
This encounter between Merlyn and Lancelot is uncomfortable and the only time the two will meet—indeed it is the last time Merlyn appears in the novel. Merlyn is confused about time—not knowing whether Lancelot has yet even met Guenever. Regardless, his visit spurs Lancelot into action and forces him to flee to Camelot. Merlyn is himself ensnared by his own fate, as he knows that Nimue will end up trapping him in a cave for hundreds of years, yet he is so in love with her he cannot stop himself from going with her.