Chapter 1 Meanwhile Mordred has been given responsibility for Guenever. He writes fake letters from across the sea that say Arthur has been killed in battle. Mordred makes a feast and has the lords choose him king. He takes Guenever as his wife: she privately mourns, but publicly agrees. She asks him to buy things for the wedding in London. While he’s gone, she encloses herself in the Tower of London, and is defended by many. Mordred lays siege to the Tower of London, but the Bishop of Canterbury tells him it is shameful for him to marry Guenever, his aunt: besides, it’s not certain if Arthur is actually dead. Mordred cries that he’ll cut off the Bishop’s head, so the Bishop flees.
We are now meant to recall the prophecy of Merlin: it has never been a secret that Mordred would eventually turn against and kill his father, even though previously he had been a loyal knight. Now, taking advantage of Arthur’s distance from court, Mordred begins to put his treacherous plans into action. Mordred is shown to be another knight who cares little for the knightly code of honor—even the warnings of the Archbishop of Canterbury, a holy man, are not enough to dissuade him from his desire for Guenever (which seems to really be a desire for power).
Then Mordred hears that Arthur (who is alive) has heard of his siege, and is pausing the fight with Launcelot to avenge himself on Mordred. Mordred draws many knights to fight with him, since many lords now think that life with Arthur is one of constant war, and they’d do better to fight for Mordred.
Mordred already knew that Arthur was likely still alive, and now his goal is to seize the throne. Other knights too are sensing that Arthur’s regime is crumbling, and they opportunistically change sides.
Chapter 2 Arthur comes to Dover with a great navy. A great battle takes place, and Arthur’s men drive back Mordred’s, until they flee. Gawaine is then found lying half-dead in a boat. Arthur weeps of sorrow, crying that he’s now lost Gawaine and Launcelot, the two men he most loves. Gawaine cries that he caused all this pain and war. He asks for pen and paper, and writes to Launcelot that he’s been mortally wounded at the site of the wound that Launcelot gave him. He writes that his death was his own fault, not Launcelot’s, and asks Launcelot to return to Camelot to pray for his soul. At noon, Gawaine dies. The king has him buried in a chapel within Dover Castle.
Now Arthur is caught between two competing battles, one with Gawaine against Launcelot, and one against his own son and knight Mordred. Only on Gawaine’s deathbed does he appear to fully understand the implications of what he’s done. His furious jealousy seems to have been a kind of enchantment preventing him from seeing clearly, and that spell is only now lifted. Although Gawaine dies repenting, he has put into action an unstoppable chain of events.
Chapter 3 Arthur’s men battle Mordred’s once again, and then prepare to meet a third time, on an upcoming Monday. Many of those who love Launcelot join Mordred’s side. The night before the battle, Arthur dreams that he is dressed in rich gold cloth and sitting on a chair bound to a wheel. Under him is black water with serpents and wild beasts, and he suddenly falls into the water, and wakes up. When he falls asleep again, Gawaine comes to him in a dream, saying God has told him to warn Arthur that if he fights with Mordred the next day, he will be killed: Arthur must instead call a month-long truce and wait for Launcelot to arrive. When Arthur awakens, he tells his knights of the vision, and order them to make a peace treaty with Mordred for a month.
One of the consequences of Gawaine’s actions is, of course, Arthur’s war with his son Mordred. Launcelot, meanwhile, would be appalled to learn that knights who were loyal to him have now chosen Mordred. Arthur’s dreams are menacing, suggesting that he is on shaky ground in attempting to defend himself. But he trusts the correctness of these visions and seeks to do all he can to follow God’s advice (through Gawaine).
Chapter 4 Mordred agrees, but Arthur warns his knights to keep watch, since he suspects Mordred of wrongdoing. Likewise Mordred warns his men to draw their swords if they see any sword drawn. Mordred and Arthur meet to sign the treaty, but then a small snake (an adder) comes out of a bush and stings a knight, who draws his sword to kill it. When others see the sword, they blow their horns and prepare for battle, the treaty broken. There was never a worse battle than this day, though Arthur performs magnificently. Nearly all the knights from both sides are soon killed, which infuriates Arthur. He rides to Mordred, forgetting Gawaine’s warning. Mordred rides towards Arthur, who strikes him through the body. But as Mordred feels his death wound he strikes Arthur on the side of the head. They both fall to earth, Mordred dead and Arthur mortally wounded.
The truce between Arthur and Mordred is a tenuous one from the start, especially because of the mutual distrust that makes each side believe the other will act dishonorably. However, it is not through shame and deceit but through a tragic accident that the treaty is broken before it is ever made official—an accident that nonetheless seems to be fated. Arthur, in an aberration from his usual calm and thoughtful spirit, is driven to such fury by the killing of his knights that he brings about his own downfall. The prophecy of Merlin thus looks like it will be fulfilled, with the added consequence that Mordred himself also dies.
Sir Lucan and Bedivere lead Arthur to a chapel. They hear a great noise in the field, and the two knights emerge to see robbers pillaging the knights of their brooches and jewels. They tell Arthur the news.
The looting of riches is another reminder of how low the once mighty kingdom of Arthur’s has sunk, and how shame and greed have replaced honor.
Chapter 5 Arthur cries that none of this would have happened if Launcelot were here. Lucan tries to lift up Arthur, but falls on account of his own wound, and dies on the ground. Arthur tells Bedivere to take Excalibur to the riverside and throw it in the water. Bedivere departs, but says to himself that no good can come of throwing it in the water, so he hides it behind a tree. Upon his return, Arthur asks what he saw. Bedivere says he saw only waves and winds, so Arthur says he has lied, and orders him to go back. But Bedivere only hides it again: on his return, Arthur says he’s betrayed him twice. He’s about to die, he says, so he begs Bedivere to listen to him. Finally Bedivere returns and throws the sword into the water. An arm emerges from the water to grab Excalibur, and then it vanishes. Bedivere returns to Arthur and brings him to the waterside, where a barge appears with many fair ladies wearing black hoods. Bedivere puts Arthur into the barge. Then Bedivere cries that he’s been left all alone, and he weeps.
Lucan’s death is both another tragedy and a confirmation of Arthur’s cry that Launcelot would have prevented such death and destruction—except, of course, that this battle with Mordred only took place precisely because of the rift between Arthur’s court and Launcelot more generally. On a more personal note, Arthur’s lament shows how he still doesn’t hate Launcelot for his affair, and in fact still considers Launcelot his greatest friend. Arthur’s final conversation with Bedivere is one last example of just how much his knights struggle to do the honorable thing rather than lying and behaving treacherously for their own benefit. Bedivere, however, finally conquers his selfishness, which allows Arthur to die knowing that his mighty sword has returned to the mysteries from which it came (the arm that catches the sword presumably belongs to the Lady of the Lake, perhaps Nimue).
Chapter 6 Bedivere lies to rest in a hermitage, where he meets the Bishop of Canterbury, who had fled Mordred. There is a tomb next to him, and the bishop says a number of ladies brought a corpse to him at night. Bedivere cries that this was Arthur. Bedivere swears to remain here forever, and puts on poor clothes. The narrator shares that the queens on the barge were Morgan le Fay, the Queen of Northgalis, the Queen of the Waste Lands, and Nimue.
Following Arthur’s death—which is, according to the book’s title, the central event of the work—other characters struggle to figure out what his death means and how to continue on without him. For Bedivere, this means vowing to live like a poor hermit in loyalty to Arthur even after his death. Women’s power in the book also extends to their role in watching over the dead, and even the women who were antagonistic to Arthur in life now seem to assist him in death.
Chapter 7 Some men now say that Arthur is not dead, but hiding by God’s grace, and will come again. Others say that on Arthur’s tomb is written a Latin verse, saying “Here lies Arthur, once and future king.” When Guenever learns of Arthur’s death, she leaves to become a nun in Almesbury.
The narrator is careful to recognize the variety of opinions about Arthur’s death or continued life, but the book seems to privilege the idea that Arthur has, in fact, died, and that to believe otherwise is just wishful thinking.
Chapter 8 The narrator returns to an earlier moment, and says that Launcelot learns of Mordred’s treachery through Gawaine’s letter, which has grieved him deeply. Launcelot prepares to go to Gawaine’s tomb, and he arrives with his knights and mourns there. But then they learn of the deaths of both Mordred and Arthur. Launcelot cries that they’ve come too late. He tells his men to leave for their country, while he seeks out Guenever.
Launcelot has not been present for most of this tragic ending, instead remaining in his new kingdom in Bayonne. But once Gawaine is dead, there is no longer much reason for him to stay away. Launcelot only slowly learns the extent of the death and destruction that has taken place while he’s been in exile.
Chapter 9 Launcelot finds Guenever in her convent. Guenever cries that Arthur is dead because of her and Launcelot’s love. Guenever asks Launcelot never to see her again, since she has sworn to repent. She asks him to take a wife and live in his kingdom. Launcelot swears he will never be false to Guenever: indeed, he even gave up the Sangreal out of love for her.
Chapter 10 Launcelot and Guenever depart, both weeping. Launcelot rides to a hermitage, where he meets Bedivere and the Bishop, and is clothed in poor clothing as well. Sir Bors rides to this chapel, and asks to be made a holy man too. Soon many other knights join them and do penance for six years. Finally Launcelot sees a vision telling him to go to Almesbury and bury Guenever, who has died.
Now that Launcelot and Guenever understand the extent of their sin, they know that they can no longer continue their affair (even if Launcelot remains stubbornly loyal to Guenever). This is presented as a tragic end, as their love for each other remains true, but they can no longer find happiness or satisfaction in it. The knights of the Round Table, meanwhile, have given up earthly glory for quiet prayer.
Chapter 11 Launcelot goes with other knights to Almesbury. He sees the body of Guenever, and he doesn’t weep, but only sighs. He bears her body to Glastonbury, where Arthur is buried, and the Bishop sings a great Mass. As they bury her, the hermit tells Launcelot that he displeases God with such grieving. Launcelot says he doesn’t mean to, but his sorrow has no end, when he remembers Guenever’s beauty, and her and Arthur’s nobility, and his own pride and sin.
The scene in which Launcelot sees Guenever’s body for the last time is one of great pathos, and his feelings seem to exceed even the capacity to weep. The hermit, like those who chastised Launcelot throughout the Sangreal quest, knows that there is something unholy in Launcelot, but Launcelot never repents of his great love for Guenever. It’s also noteworthy that Launcelot continues to honor Arthur alongside Guenever—he didn’t consider Arthur his rival or enemy, but only his friend and king, despite the fact that they both loved the same woman.
Chapter 12 Afterward Launcelot eats and drinks little, and grows weaker and weaker. Six weeks later, he falls to bed, and sends for the Bishop to give him Christian last rites. He asks to be buried at his castle. After midnight, everyone hears the Bishop laughing. They rush to him, and he says he’s seen Launcelot being drawn up into heaven by angels. They find Launcelot dead in his bed, and all the knights carry his body to Joyous Gard to bury him.
Once Guenever is dead, Launcelot is not long for this world either. But in contrast to Guenever’s death, Launcelot’s is actually one of joy. Despite all of Launcelot’s inability to live up to spiritual holiness, the book seems to forgive him at the end, granting him the right to reach heaven even despite his sins.
Chapter 13 Sir Ector de Maris comes to Joyous Gard to see the tomb of his brother. He cries that Launcelot was never matched by any knight, and was a true friend and lover, and was good, kind, and meek. All the mourners go to the Bishop’s hermitage. Then Sir Constantine is chosen king of England. Many of Arthur’s knights leave the kingdom and live elsewhere as holy men. Others go to the Holy Land and fight against heathens, and die on a Good Friday.
As Constantine is chosen as the new king of England, the knights of Arthur scatter, and the fellowship of the Round Table is definitively finished. Other reigns and other fellowships will succeed it, but the Round Table members will live on only in the stories and legends so carefully written down and preserved.