Kurwenal appears in the women's quarters ("Auf auf! Ihr Frauen!") and announces that the voyage is coming to an end. Isolde warns Kurwenal that she will not appear before the King if Tristan does not come before her as she had previously ordered and drink atonement to her. When Tristan arrives, Isolde reproaches him about his conduct and tells him that he owes her his life and how his actions have undermined her honour, since she blessed Morold's weapons before battle and therefore she swore revenge. Tristan first offers his sword but Isolde refuses; they must drink atonement. Brangäne brings in the potion that will seal their pardon; Tristan knows that it may kill him, since he knows Isolde's magic powers ("Wohl kenn' ich Irlands Königin"). The journey almost at its end, Tristan drinks and Isolde takes half the potion for herself. The potion seems to work, but instead of death, it brings relentless love ("Tristan!" "Isolde!"). Kurwenal, who announces the imminent arrival on board of King Marke, interrupts their rapture. Isolde asks Brangäne which potion she prepared and Brangäne replies, as the sailors hail the arrival of King Marke, that it was not poison, but rather a love potion.