Ciarán regarded me in silence. After a little, he said, “You must not make him promises you intend to break. He would destroy you.”

“I won’t,” I said, though the plan might take me perilously close to it—I would have to stay alert and keep my wits about me, no matter what happened. Even if Mac Dara hurt me. Even if he hurt Cathal. I hoped I was strong enough.

“By all the gods,” muttered Ciarán. “I wish there were some way I could aid you further.”

“It’s probably better not,” I made myself say. “I let Cathal help me, and look what’s happened to him. I do have a question.”

“Ask it, Clodagh.”

“That charm, the verse . . . If there are three or four versions of the story, and the last two lines are different in each one, how can I know which one Mac Dara spoke when he worked the spell over Cathal? Supposing we could make ancient enemies into friends, and somehow tame the sea, impossible as that sounds. Mac Dara could turn around and say he didn’t use that version of the rhyme, but one in which the last part was something different. You’ll be mine forever more, until the stars tumble from the sky and Eilis volunteers to do the mending. It could be anything at all.”

My attempt at humor had brought a faint smile to Ciarán’s lips. “If that was the story as the old woman told it,” he said, “then that is the correct version of the rhyme. Willow gave you the key to undoing the charm. It seems she wished to help this much younger brother of hers. That she did so cryptically, through a tale, was doubtless for her own protection. Mac Dara’s anger is greatly to be feared. Should the last part of the rhyme become true, he will be obliged to let his son go. How could an old woman know such a thing? I expect there were witnesses to the casting of the charm. If a wandering storyteller asked those witnesses a question or two, why wouldn’t they answer? Mac Dara has at least one weakness. Over the years, it seems he has underestimated women.”

“But,” I protested, finding it almost too much to take in, “Willow told that story a long time ago, well before Cathal and I went to the Otherworld. How could she know what spell Mac Dara was going to use? And why couldn’t she just explain to Cathal the danger he was in?”