"I took them from him, it's true," said the knight; "but it would be hard for me to give them to you now; for a man came and took them from me, who would have taken them from you and all that are with you, and as many more if they had been here before him."
"Who in the world could that man be?" asked Cucúlin.
"The Dark Gruagach of the Northern Island. Release me, and come to my castle. I'll tell you all and entertain you well."
He took them to his castle, gave them good cheer, and told them all about the Gruagach and his island. Next morning all sailed away in Cucúlin's vessel, which they had left at the shore of the island, and never stopped till they came to the Gruagach's castle, and pitched their tents in front of it.
Then Cucúlin challenged the Gruagach. The others followed after to know would he thrive. The Gruagach came out and faced Cucúlin, and they began and spent the whole day at one another and neither of them gained the upper hand. When evening came, they stopped and prepared for supper and the night.
Next day after breakfast Cucúlin challenged the Gruagach again, and they fought till evening; when Cucúlin got the better in the struggle, disarmed the Gruagach, bound him, and said: "Unless you give up the rod of enchantment and the ring of youth that you took from the knight of the island of the Flood, I'll cut the head off you now."
"I took them from him, 'tis true; but there was a man named Thin-in-Iron, who took them from me, and he would have taken them from you and from me, and all that are here, if there were twice as many. He is such a man that sword cannot cut him, fire cannot burn him, water cannot drown him, and 'tis no easy thing to get the better of him. But if you'll free me now and come to my castle, I'll treat you well and tell you all about him." Cucúlin agreed to this.
Next morning they would not stop nor be satisfied till they went their way. They found the castle of Thin-in-Iron, and Cucúlin challenged him to combat. They fought; and he was cutting the flesh from Cucúlin, but Cucúlin's sword cut no flesh from him. They fought till Cucúlin said: "It is time now to stop till to-morrow."
Cucúlin was scarcely able to reach the tent. They had to support him and put him to bed. Now, who should come to Cucúlin that night but Gil an Og, and she said: "You have gone further than any man before you, and I'll cure you now, and you need go no further for the rod of enchantment and the ring of youth."
"Well," said Cucúlin, "I'll never give over till I knock another day's trial out of Thin-in-Iron."