Osan drove us inland again, into a valley where the roads grew rockier and the horses moved more slowly. I guessed that we had crossed into the Rutese province; I wasn’t familiar with the area, I’d never travelled this far west from the city. The miles crawled by, and I tried my best not to think, not to imagine what was going to happen next.

The road came to an end at a circular clearing below a sheer rockface. Coarse grey thorn brush surrounded us. Osan stopped the horses and climbed down from his seat. Cyde opened the door.

“Where are we?” I asked.

“Officially? Nowhere.” She walked over to the thorny bushes at the base of the cliff, and swept them aside with her lace. Hidden behind the dry branches was a narrow passage cut into the rock. “The Ash Disciples built this place four hundred years ago during their revolt against the Order. While serving as Chief Archivist, I came across a mention of it and decided to investigate whether the passages were still intact.”

The entrance was high enough to accommodate a tall man, although Finn still needed to stoop. Water dripped loudly and a strong animal musk lingered in the air. It was pitch dark ahead.

“Apart from a small cave-in, the main passages were untouched,” said Cyde. “Remarkable, really, that it survived.”

“So the Order doesn’t know about this place?” asked Millie.

“Outside of the people I’ve told, no. We should be safe here until Celane is forced to play her hand. That gives us time to prepare.”

Prepare for what?

Finn helped Cyde light the lamps, and the passage brightened. To my surprise, the room ahead was large and ornate. Intricate mosaics covered the walls—the patterns looked familiar, the abstract curves and swirls of the designs curling like vines. I had seen these designs elsewhere. I noticed Cyde was watching me.

“The Ash Disciples didn’t build this,” I said slowly.

She nodded.

“The mosaics…” I walked over to the wall. “They match the ones in the Martyrium. This is Sisterhood insignia. Old-fashioned, but still very similar.”

“It is, yes.”

“But how can that be?”

“I have a theory. I’ll explain after I’ve shown you where you’ll be sleeping.”

I trailed my fingers over the tiles. Strange. I was certain this could not be the work of insurgents—why adorn their hideout with the enemy’s symbols? why decorate at all?—but neither could the Sisterhood have built the place and then simply forgotten it existed.

The mosaics continued in the next room, a larger hall where it was drier and the sound of the rain diminished to a soft hushing. Three other passages led off deeper into the hillside.

“There’s dried meat and preserves over there, lantern oil in the canisters, and blankets in the next chamber,” said Cyde, pointing. “You should be comfortable enough, but use the food and oil sparingly; it might be difficult for me to bring more supplies over the coming days.”