“Iris, give it a chance,” Matt said.

“A chance for what? It’s hopeless! We’re driving around a place I’ve never seen before, wasting time while anything could be happening to Hayley!”

As if he’d caught her impatience, Matt sped up, driving a little too fast to go through town. He cut down a steep alley between two buildings that took us closer to the water, onto the service road that ran behind shops and restaurants.

“Wait!” Iris shouted. “Back up!”

Matt jammed on the brakes and put the Jeep into reverse. The tires jounced on the road’s cobblestones. Iris grabbed my shoulder with one hand and began pointing wildly with the other. Matt stopped the car and we all stared.

Iris was pointing at a stone-and-concrete wall that formed the basement level of the old buildings on Bank Street. The wall was weathered by centuries of fog and salt air, with some stones tilted and coming loose, and the mortar crumbling.

“What are we looking at?” I asked.

“Ghost signs,” Iris said. “Advertisements painted years and years ago. They’re so faded they’re barely visible. I grew up seeing ones like these.”

As I stared, the faint colors materialized on the dusty wall. Therewerefaded signs there! Most were advertisements connected to the nautical world: a sailmaker’s loft, a ship chandlery, a master carver of figureheads, the Whalers Tavern, the Barquentine Pub.

But there was also a life-sized depiction of three girls dressed in long white gowns—the paint was so faded, the girls looked like teenaged apparitions. All three of them had ethereally beautiful faces, with wide eyes and mysterious smiles. Their arms were linked, and they had flowers in their long hair. In spidery print above them were the wordsSibylline Sisters: Oracles. And the date:1944.

“The girls are the same,” Iris said, staring. She opened the Jeep door and got out. She stood in front of the ghost sign of the girls.

“The same as what?” Matt asked as he and I climbed out to stand beside her.

“As the ones on the panels.”

“What panels?” I asked.

“The goddesses,” she replied.

“This is too bizarre,” Matt said, giving me a look as if he thought Iris might be losing her mind. “Goddesses?”

“There were panels painted with classical-looking girls,” Iris explained. “Young women. They were wearing long white dresses. Pleated gowns, exactly like these.” She pointed to the ghost sign. “Remember, Oli? I told you about them?”

“You mentioned paintings,” I said.

“Yes,” she said, impatiently. “But they were painted on panels—tall pieces of board, taller than I am.”

“Where are these panels?” Matt asked.

“In the place where he kept us.”

“Kept you?” I asked, my heart pounding. “You remember now?”

She nodded. “Sort of. I’m starting to . . . Up all those flights of stairs. Up in the attic.”

“Attic of what?” Matt asked.

Iris gave him a desperate look. “If I knew, do you think we’d be standing here? I’d be running as fast as I could to save Hayley.”

“That’s where Hayley is now?” I asked.

“Unless they moved her,” she said.

“When you say ‘they’ . . .” Matt said. “Who do you mean?”

Iris didn’t answer at first. During her silence, I noticed that Matt was busy texting. Then Iris pointed at the spectral figures again. “These girls on this ghost sign areexactlythe same as the ones on the panels,” she said. “And the girl in the bed was dressed almost the same way, in a long white nightgown.”

Wait.