Gaheris and other Round Table knights visit King Mark's court and report Tristram's great deeds. While they are there a challenge comes to Mark's court from Ywain of the Round Table. None of Mark's knights can withstand him, and the visiting Round Table knights are sworn never knowingly to ride against a fellow Round Table knight except in sport. In idiotic fury, Mark himself attacks Ywain — from ambush. Kay scoffs at Mark's cowardice and rebukes him for sending his best knight, Sir Tristram, into exile. Spitefully, Mark and Andret decide to waylay Kay and Gaheris. They put on black clothes so that they won't be seen in the dark, forgetting that it is a bright moonlit night. Kay and Gaheris easily trounce them.
Meanwhile the jailor of Tristram, Palomydes, and Dynadin reconsiders and releases the knights from prison. Dynadin encounters the murderer of knights, Bereuse Saunz PitŽ (whose later death at Gareth's hands has already been recounted), and puts him to flight. Tristram falls into Morgan's hands and is tricked into bearing for her a shield designed to embarrass Launcelot and Guinevere. He uses the shield in a tournament where he unhorses both Arthur and Ywain.
