Finn, in his old age, asked the hand of Grainne, the daughter of Cormac Mac Airt; but the lady being young, preferred a younger lover.

To effect her purpose, she drugged the guest-cup so effectually, that Finn, and all the guests invited with him, were plunged into a profound slumber after they had partaken of it.

Oisin and Diarmaid alone escaped, and to them the Lady Grainne confided her grief.

As true knights they were bound to rescue her from the dilemma.

Oisin could scarcely dare to brave his father's vengeance, but Diarmaid at once fled with the lady.