There they find not only the headless dragon, but the unconscious Tristram, and the tongue which proves him the real victor.

To nurse him back to health is no great task for these ladies, who, like many of the heroines of the mediaeval epics and romances, are skilled leeches and surgeons.
One day, while guarding their patient's slumbers, the ladies idly examine his weapons, and make the momentous discovery that the bit of steel found in Morolt's head exactly fits a nick in Tristram's sword.
Although both had sworn vengeance, they decide the service Tristram has just rendered them and their country more than counterbalances the rest, and therefore let him go unscathed.
Fully restored to health, Tristram proves the butler had no right to Iseult's hand, and, instead of enforcing his own claim, makes King Mark's proposals known.

Either because such an alliance flatters their pride or because they dare not refuse, Iseult's parents accept in their daughter's name and prepare everything for her speedy departure.

The queen, wishing to save her daughter from the curse of a loveless marriage, next brews a love-potion which she bids Brengwain--her daughter's maid and companion--administer to King Mark and Iseult on their wedding night.
During the trip across the Irish Channel, Tristram entertains Princess Iseult with songs and tales, until he becomes so thirsty that he begs for a drink.

By mistake the love-potion is brought, and, as Iseult graciously dips her lips in the cup before handing it to her entertainer, it comes to pass both partake of the magic draught, and thus become victims of a passion which naught can cure.