“I noticed it when we came back up on deck,” said Cathal, and I saw on his face that he was starting to follow our thinking. “I didn’t make much of it at the time—I wasn’t sure. Then Gareth asked me if I’d noticed a difference; he’d felt it, too.”

We sat silent for a while, listening to the scream of the gale and the pounding of the waves against the hull. Eventually I said, “She knows the way. Svala knows the way. Gareth must untie her and let her go back up on the prow. It doesn’t matter, for now, who’s stirring the seas and making the wind blow. Without Svala, we won’t find the serpent isle.”

“The wind changed because she was not there to guide us?” Gull sounded somewhat sceptical. “What is she, a goddess?”

“I don’t understand it either, Gull, but my instincts tell me this is what we must do. Tell Gareth, Cathal, and get her back up there quickly, before we go too far off course.” I realized I was giving orders. “Please tell him I’m sure that’s what he must do.”

“Felix?” Cathal lifted his brows. “You concur with this?”

“I do,” Felix said. “The sooner Svala is set free, the sooner we will reach that place. Perhaps today. Perhaps today we will find them.”

Cathal went on deck. Very soon after, he came down again. “He’s prepared to try it. Felix, will you untie Svala’s bonds?”

I had not thought it possible for Felix to go any paler, but he did so now. “I will,” he said. “Sibeal, I may need your help.”

I stood by Svala, using gestures to explain as best I could what was happening. My link with her was weak here in the hold; there were, perhaps, too many others close by to allow that joining of thoughts we had sometimes shared. But I could keep her calm while Felix undid the knots and freed her hands. I could murmur to her while he knelt to unfasten the ropes around her ankles. It was a slow job; his hands were shaking. I understood why Cathal had laid this particular duty on him.

“It’s done,” Felix said eventually, and rose to his feet. Tears were running down his cheeks. “You’re free.”

I had expected Svala to dart away as soon as the last knot was untied. But she laid her hands on Felix’s shoulders—she was slightly taller than he—and nodded gravely in recognition. Then she took my arm and pointed up to the deck, giving voice to a sequence of liquid sounds that were somewhere between speech and song. A series of clear gestures followed: you, me, up there. Then a sweeping, almost imperious movement of the arm, indicating Felix. And him. She motioned to Gull. That one, too.