Forthwith, King Arthur sent for his nephew, Sir Gawain, and said to him: "Fair nephew, I give it in charge to you to see that all is done as has been decreed." But Sir Gawain answered boldly: "Sir King, never will I be present to see my lady the Queen die. It is of ill counsel that ye have consented to her death." Then the King bade Gawain send his two young brothers, Sir Gareth and Sir Gaheris, to receive his commands, and these he desired to attend the Queen to the place of execution. So Gareth made answer for both: "My Lord the King, we owe you obedience in all things, but know that it is sore against our wills that we obey you in this; nor will we appear in arms in the place where that noble lady shall die"; then sorrowfully they mounted their horses, and rode to Carlisle.
When the day appointed had come, the Queen was led forth to a place without the walls of Carlisle, and there she was bound to the stake to be burnt to death. Loud were her ladies' lamentations, and many a lord was found to weep at that grievous sight of a Queen brought so low; yet was there none who dared come forward as her champion, lest he should be suspected of treason. As for Gareth and Gaheris, they could not bear the sight and stood with their faces covered in their mantles. Then, just as the torch was to be applied to the faggots, there was a sound as of many horses galloping, and the next instant a band of knights rushed upon the astonished throng, their leader cutting down all who crossed his path until he had reached the Queen, whom he lifted to his saddle and bore from the press. Then all men knew that it was Sir Launcelot, come knightly to rescue the Queen, and in their hearts they rejoiced. So with little hindrance they rode away, Sir Launcelot and all his kin with the Queen in their midst, till they came to the castle of the Joyous Garde where they held the Queen in safety and all reverence.
But of that day came a kingdom's ruin, for among the slain were Gawain's brothers, Sir Gareth and Sir Gaheris. Now Sir Launcelot loved Sir Gareth as if he had been his own younger brother, and himself had knighted him; but, in the press, he struck at him and killed him, not seeing that he was unarmed and weaponless; and in like wise, Sir Gaheris met his death. So when word was brought to King Arthur of what had passed, Sir Gawain asked straightway how his brothers had fared. "Both are slain," said the messenger. "Alas! my dear brothers!" cried Sir Gawain; "how came they by their death?" "They were both slain by Sir Launcelot." "That will I never believe," cried Sir Gawain; "for my brother, Sir Gareth, had such love for Sir Launcelot that there was naught Sir Launcelot could ask him that he would not do." But the man said again: "He is slain, and by Sir Launcelot."