In Book I, “The Sword and the Stone,” we are introduced to the Wart, a young boy who eventually becomes King Arthur. The Wart grows up in the castle of Sir Ector, his foster father. The Wart spends his days in the company of Kay, Sir Ector’s son and the heir to his title, amusing himself as best he can while Kay is instructed in the proper ways of knighthood. One night while lost in the forest, the Wart encounters the magician Merlyn, a befuddled but powerful old man who announces that he will be the Wart’s tutor. During the next six years, Merlyn tries to instill some of his wisdom in the Wart, teaching him about virtue and the world by turning the Wart into various animals. Finally, Kay is knighted, and the Wart becomes his squire, a kind of servant who assists and attends to his master as the knight travels in search of adventure. When the king of England, Uther Pendragon, dies, he leaves no heir, and it is proclaimed that the next rightful king will be whoever can pull out a mysterious sword that has been driven into a rock. The Wart and Kay travel to London, where a tournament is being held so that the finest knights will have the opportunity to try to remove the sword. While running an errand for Kay, the Wart removes the sword from the stone, and he is declared the next king of England.
Book II, “The Queen of Air and Darkness,” finds the young King Arthur, as the Wart is now called, trying to hold on to his power. Of the men rebelling against Arthur, his most notable enemy is King Lot of Orkney. As the war rages on in England, Lot’s sons, Gawaine, Gaheris, Gareth, and Agravaine, compete for the affections of their mother, the beautiful but cruel Morgause. By a twist of fate, Morgause is also Arthur’s half-sister, though he does not know it. Three knights from Arthur’s court arrive at Orkney, and unaware that their king is at war with Lot, they proceed to bumble around the countryside. Although Gawaine, Gaheris, and Gareth are all decent at heart, they and their brother, Agravaine, are happiest when they are listening to stories about their proud heritage and dreaming about wars and bloody revenge.
In England, Arthur begins to plan how he will rule when the battles are finally over. With Merlyn’s guidance, he decides to use his own power and that of his fellow knights to fight for people who cannot defend themselves. Arthur creates an order of knights to fight for good, called the Knights of the Round Table. Then, with the help of two French kings, Bors and Ban, Arthur defeats Lot’s army at the battle of Bedegraine. With her four children, Morgause travels to Arthur’s court, supposedly to reconcile Arthur with Lot. While at the court, she uses magic to seduce Arthur. Arthur is not aware that Morgause is his half-sister, but the incest is still a great sin, and by sleeping with her, Arthur ultimately brings about his own destruction.
Book III, “The Ill-Made Knight,” focuses on the great knight Lancelot and his moral conflicts. Lancelot is just a boy when King Arthur takes the throne, but he eventually becomes Arthur’s greatest knight and best friend. Trying to escape his growing feelings for Queen Guenever, Lancelot embarks on a series of quests that establish his reputation. In the last of these, he is tricked into sleeping with a young girl named Elaine. Guenever grows increasingly jealous of Elaine, and her jealousy eventually drives Lancelot insane. He roams England for several years as a wild man, unrecognized and ill-treated by everyone he meets. Finally, Elaine discovers Lancelot and nurses him back to health. Although Lancelot does not want to feel obligated to Elaine, he does, and on two occasions he leaves Camelot to spend time with her and their son, Galahad. Meanwhile, Arthur’s kingdom begins to unravel, and he tries to keep his knights occupied by sending them to find the Holy Grail. Only three knights, Sir Bors, Sir Percival, and Sir Galahad, are pure enough to find the holy vessel. Lancelot returns a humbled and deeply religious man. For a while, his love for God makes him stay away from Guenever, but after he rescues her from a kidnapper, they begin their affair again.
In Book IV, “The Candle in the Wind,” the destruction of Camelot becomes inevitable. Mordred, Arthur’s son by his incestuous union with Morgause, plots revenge against his father. Mordred and Agravaine trap Arthur into acknowledging the affair between Lancelot and Guenever, which forces Arthur to prosecute his queen and his best friend. Lancelot rescues Guenever from being burned at the stake, but in doing so, he kills two of Gawaine’s brothers, Gareth and Gaheris. Arthur and his armies lay siege to Lancelot’s castle. The pope sends an emissary to broker a truce, and Guenever returns to Arthur’s castle at Camelot. Arthur and Gawaine, however, still want to avenge the deaths of Gareth and Gaheris, and they continue to besiege Lancelot. While they are away, Mordred usurps the throne. Arthur rushes back to reclaim his kingdom. The night before his final stand against Mordred, Arthur reflects on all he has learned since his youth and wakes up confident that although this day will be his last, his legacy will live on.