The Conspiracy of Morgan le Fay
When Arthur, King Urien and Accolon of Gaul (France) went hunting for a hart, they came upon a ship, filled with women. They were entertained on board. As each of them retired for the night in separate chambers, Urien was magically transported back to Camelot, while Arthur found himself in prison of unknown castle that belonged to Sir Damas.
The damsel told Arthur that he could gain freedom if he fight in single combat. This young woman was actually Morgan le Fay, disguised as an ordinary damsel. Morgan le Fay also visited Accolon who became her lover. She asked Accolon to fight a knight, and give her enemy’s head to her. Morgan gave her lover, Excalibur and Arthur’s magic scabbard. While she gave the bogus Excalibur and scabbard to her brother.
When Arthur engaged the other knight, he did not recognise Accolon. They fought until Arthur realised he had been betrayed. His sword did no damage to Accolon, while he received wounds from his enemy. He realised his sword was counterfeit. He tried to bravely defend himself as best he can, but his shield was soon in tatter, while he received many wounds. What was even worse, was that Arthur’s sword (the fake Excalibur) broke in two. Rather than yielding to his enemy, Arthur rushed at his enemy with what left of his shield.
The timely arrival of Niniane (Nimue), the Lady of the Lake, saved Arthur’s life. Niniane knew that Morgan le Fay was plotting her own brother’s death, because Merlin had told her. Niniane cast a spell, which caused Accolon to drop Excalibur to the ground. Arthur immediately seized the advantage, regaining Excalibur. Arthur then set about defeating his enemy. Accolon was mortally wounded.
Arthur then discovered the identity of his opponent. Accolon told of how Arthur’s sister stolen Excalibur from him. Accolon confessed that when Arthur was killed in combat, then she would murder her husband, King Urien of Gorre. Thereupon, she would marry and make Accolon, who will become king of Logres and Gorre. By night-time Accolon had died from his wound.
Morgan le Fay thought her brother was dead. At night, she was going to murder her husband, while Urien was asleep. Their son, Yvain, discovered the plot against his father. Yvain rescued his father, but he would not harm his mother. Yvain allowed his mother (Morgan) to escape.
The next day, Morgan le Fay heard news that Arthur had survived and was now returning to Camelot, and that her lover (Accolon) had died. When Arthur was asleep in an abbey, Morgan went into her brother’s room to steal Excalibur again. But Arthur had slept with Excalibur in his hand, so Morgan stole the magic scabbard, before fleeing.
When Arthur woke and found that his sister had stolen his scabbard, he set off in pursuit. Before Arthur could catch her, she threw the scabbard into the lake. Then she changed herself and her attendants to look like rocks. Not able to find her, Arthur was forced to continue his journey to Camelot without his magical scabbard.
Later, Morgan sent one of her damsels to her brother, in Camelot. The damsel brought to Arthur a beautiful robe, as a gift and peace offering. Arthur accepted, but Niniane, the Lady of the Lake, advised Arthur not to wear the robe. Arthur immediately ordered the damsel to wear the robe. The damsel reluctantly put on the robe and immediately died. Arthur was angry that his sister was still seeking his death.
At Camelot, Arthur knew his brother-in-law (Urien) was innocent of his sister’s plot against him, since Accolon said that Morgan wanted to kill her husband. However, he was uncertain about the innocence and loyalty of his nephew Yvain. Arthur banished his nephew from his court.
Gawain loved his cousin, enough to accompany Yvain in an adventure where they meet the Irish knight Marhaus (Thomas Malory called him Morholt). After the companions’ individual adventure of the three damsels of the fountain was completed, Arthur welcomed Yvain back to the Round Table, and Marhaus also became the newest member of the fellowship of the Round Table. (See Three Damsels of the Fountain for the full account of the adventures of Gawain, Yvain and Marhaus in Sir Gawain.)