Book IX - Chapter XVI - How King Arthur was brought into the Forest Perilous, and how Sir Tristram saved his life.
NOW shall ye hear what was the cause that King Arthur came into the Forest Perilous, that was in North Wales, by the means of a lady. Her name was Annowre, and this lady came to King Arthur at Cardiff; and she by fair promise and fair behests made King Arthur to ride with her into that Forest Perilous; and she was a great sorceress; and many days she had loved King Arthur, and because she would have him to lie by her she came into that country. So when the king was gone with her many of his knights followed after King Arthur when they missed him, as Sir Launcelot, Brandiles, and many other; and when she had brought him to her tower she desired him to lie by her; and then the king remembered him of his lady, and would not lie by her for no craft that she could do. Then every day she would make him ride into that forest with his own knights, to the intent to have had King Arthur slain. For when this Lady Annowre saw that she might not have him at her will, then she laboured by false means to have destroyed King Arthur, and slain.
Then the Lady of the Lake that was alway friendly to King Arthur, she understood by her subtle crafts that King Arthur was like to be destroyed. And therefore this Lady of the Lake, that hight Nimue, came into that forest to seek after Sir Launcelot du Lake or Sir Tristram for to help King Arthur; foras that same day this Lady of the Lake knew well that King Arthur should be slain, unless that he had help of one of these two knights. And thus she rode up and down till she met with Sir Tristram, and anon as she saw him she knew him. O my lord Sir Tristram, she said, well be ye met, and blessed be the time that I have met with you; for this same day, and within these two hours, shall be done the foulest deed that ever was done in this land. O fair damosel, said Sir Tristram, may I amend it. Come on with me, she said, and that in all the haste ye may, for ye shall see the most worshipfullest knight of the world hard bestead. Then said Sir Tristram: I am ready to help such a noble man. He is neither better nor worse, said the Lady of the Lake, but the noble King Arthur himself. God defend, said Sir Tristram, that ever he should be in such distress. Then they rode together a great pace, until they came to a little turret or castle; and underneath that castle they saw a knight standing upon foot fighting with two knights; and so Sir Tristram beheld them, and at the last the two knights smote down the one knight, and that one of them unlaced his helm to have slain him. And the Lady Annowre gat King Arthur's sword in her hand to have stricken off his head. And therewithal came Sir Tristram with all his might, crying: Traitress, traitress, leave that. And anon there Sir Tristram smote the one of the knights through the body that he fell dead; and then he rashed to the other and smote his back asunder; and in the meanwhile the Lady of the Lake cried to King Arthur: Let not that false lady escape. Then King Arthur overtook her, and with the same sword he smote off her head, and the Lady of the Lake took up her head and hung it up by the hair of her saddle-bow. And then Sir Tristram horsed King Arthur and rode forth with him, but he charged the Lady of the Lake not to discover his name as at that time.
When the king was horsed he thanked heartily Sir Tristram, and desired to wit his name; but he would not tell him, but that he was a poor knight adventurous; and so he bare King Arthur fellowship till he met with some of his knights. And within a while he met with Sir Ector de Maris, and he knew not King Arthur nor Sir Tristram, and he desired to joust with one of them. Then Sir Tristram rode unto Sir Ector, and smote him from his horse. And when he had done so he came again to the king and said: My lord, yonder is one of your knights, he may bare you fellowship, and another day that deed that I have done for you I trust to God ye shall understand that I would do you service. Alas, said King Arthur, let me wit what ye are? Not at this time, said Sir Tristram. So he departed and left King Arthur and Sir Ector together.