Tristram's capture and escape from Cornwall is a reversal from exposure and apparent execution to a precarious escape, followed by the rescue of La Beale Isoud and a renewed separation. The episode turns on his physical resourcefulness, but it does not secure the lovers' freedom: King Mark recaptures Isoud, and Tristram's poisoned wound carries the story onward to Brittany.

Capture and Judgment

Sir Andred, Tristram's cousin, watches for the moment Tristram visits La Beale Isoud. He recruits twelve knights and surprises the couple; Tristram is seized and bound hand and foot. With King Mark's agreement, Andred and some of the barons have him taken under guard by forty knights to a chapel on the sea rocks, where he is to receive judgment.

Facing what seems an unavoidable death, Tristram appeals to the knights' sense of obligation. He reminds them that he fought Sir Marhaus over Cornwall's tribute when they had all refused the battle, and argues that allowing him to die in this manner would bring shame upon knighthood. Andred rejects his appeal and calls him a traitor. Tristram answers that Andred is his kinsman, yet has become his enemy; he also insists that, if they were alone, Andred would not dare put him to death. The family bond, invoked as a reason for restraint, instead sharpens the betrayal.

Escape from the Chapel

When Andred draws his sword to kill him, Tristram pulls his bound hands toward himself and frees them from the two knights holding him. He seizes Andred's sword, knocks Andred down, and fights until he has killed ten of the knights. The violence breaks the immediate attempt to execute him, but it cannot hold back the much larger crowd gathering in support of Andred.

Tristram reaches the chapel and defends it, then recognizes that he is unarmed and that more than a hundred people are drawing near. He shuts the chapel door, breaks the bars of a window, and leaps out onto the sea crags. Andred and his followers cannot reach him there. The escape is a change in circumstance, not a settled victory: Tristram has evaded the crowd, but remains exposed and apart from his companions.

Isoud's Rescue and Recapture

Gouvernail, Sir Lambegus, and Sir Sentraille de Lushon search for their master. On learning that he has escaped, they find him on the rocks and pull him up with towels. Tristram immediately asks where Isoud is, fearing Andred's people have taken her away. Gouvernail tells him that she has been placed in a lazar-house, and Tristram resolves not to leave her there. With his men, he takes her away and brings her to a manor in the forest.

Tristram sends his other men away, and only Gouvernail remains with him. During this period, an unnamed man whose brother Tristram had previously killed finds Tristram asleep in the forest and shoots him through the shoulder with an arrow. Tristram wakes and kills the attacker. Meanwhile, word reaches King Mark that Tristram and Isoud are at the manor. Mark arrives with many knights, but Tristram has already gone. Mark takes Isoud home and keeps her so strictly that neither she nor Tristram can send word to the other. The rescue therefore restores their immediate companionship only briefly; Mark's intervention reimposes separation.

The Wound and the Journey to Brittany

Returning to the old manor, Tristram sees the tracks of many horses and understands that Isoud has been taken. He suffers deeply at her loss, while the arrow wound causes prolonged pain because it is poisoned. Isoud, though held apart from him, finds a means to send help: through a lady related to Dame Bragwaine, she tells Tristram that she cannot heal him and directs him to King Howel of Brittany, whose daughter Isoud la Blanche Mains can.

Tristram and Gouvernail secure a ship and sail to Brittany. King Howel welcomes Tristram when he learns who his visitor is. Tristram explains that he has come for his daughter's help, having been told that she alone can heal him; Isoud la Blanche Mains does so. The episode thus ends with the wound treated and Tristram received at a new court, while La Beale Isoud remains in Cornwall under King Mark's control.

Narrative Significance

The sequence makes rescue and reversal inseparable. Tristram escapes a judgment arranged by his own king and kin, then uses his freedom to recover Isoud; almost at once, the lovers are separated again. His appeal to the knights' memory of his service for Cornwall fails to change their course, while his own combat skill succeeds only long enough to create an opening for escape.

The movement from the sea-rock chapel to the forest manor and then across the sea to Brittany also changes the form of the danger. First Tristram faces a public execution, then a sudden attack and a poisoned wound, and finally the enforced loss of contact with Isoud. The ending resolves the immediate physical crisis through healing, but not the conflict that began with their discovery: Tristram's departure gives him a way to recover, while Mark's confinement of Isoud leaves their separation in place.