Sir Tor proved before long by his gallant deeds that he was worthy to sit in one of the two empty seats of the Round Table. Many of the other Knights went out also in search of adventures, and one of them, Sir Pellinore, brought a damsel of the lake to Arthur's Court, and when Merlin saw her he fell in love with her, so that he desired to be always in her company. The damsel laughed in secret at Merlin, but made use of him to tell her all she would know, and the wizard had no strength to say her nay, though he knew what would come of it. For he told King Arthur that before long he should be put into the earth alive, for all his cunning. He likewise told the King many things that should befall him, and warned him always to keep the scabbard as well as the sword Excalibur, and foretold that both sword and scabbard should be stolen from him by a woman whom he most trusted. 'You will miss my counsel sorely,' added Merlin, 'and would give all your lands to have me back again.' 'But since you know what will happen,' said the King, 'you may surely guard against it.' 'No,' answered Merlin, 'that will not be.' So he departed from the King, and the maiden followed him whom some call Nimue and others Vivien, and wherever she went Merlin went also.

They journeyed together to many places, both at home and across the seas, and the damsel was wearied of him, and sought by every means to be rid of him, but he would not be shaken off. At last these two wandered back to Cornwall, and one day Merlin showed Vivien a rock under which he said great marvels were hidden. Then Vivien put forth all her powers, and told Merlin how she longed to see the wonders beneath the stone, and, in spite of all his wisdom, Merlin listened to her and crept under the rock to bring forth the strange things that lay there. And when he was under the stone she used the magic he had taught her, and the rock rolled over him, and buried him alive, as he had told King Arthur. But the damsel departed with joy, and thought no more of him: now that she knew all the magic he could teach her.