“Where is she now?” demanded Dianda. “Where are my sons?”

“I don’t know. But I’m going to find out.” I dropped the scrap of paper back into the dish, straightening.

Dean’s room yielded nothing else of interest, although I’m pretty sure he wouldn’t have been happy to see me rooting through his underwear drawer. Eventually, even Dianda had to admit that we were done, and we moved across the hall to Peter’s room.

If Dean was a budding scholar dreaming of the land, Peter was a normal twelve year old, and even Helmi’s valiant efforts to tame his room had failed. I knew as soon as I crossed the threshold that he was a collector of shells, a lover of strange stones, and an explorer of sunken ships—unless he’d managed to acquire his impressive assortment of coins, cannonballs, and other shipwreck souvenirs online, which I doubted. He didn’t have a bed; instead, a deep saltwater pool about the size of a hotel hot tub sat at the center of the room, with handgrips around the edges to make it easier to get in and out of.

And none of that mattered, because the smell of blood punched me in the nose as soon as the door was opened. I grabbed the doorframe, half-staggering. Connor caught my shoulder, lending a bit of extra stability.

“What is it?” Dianda demanded. “What’s wrong?”

“Blood,” I said, trying to make my eyes focus. “Someone’s been using blood magic here.”

“That’s impossible. If someone had, we’d know.”

“Maybe not,” said Patrick. “Amandine could find a single drop of blood in a field of love-lies-bleeding. I saw her do it once, at a summer festival. It was a party trick for her.”

“She was a pureblood. October is a changeling.”

“Not where blood is concerned,” said Connor staunchly.

I barely heard them. I was too busy trying to sort through the conflicting information I was receiving from the room, which smelled like blood that wasn’t blood, and magic that wasn’t magic. I shrugged off Connor’s hand and started forward, not allowing myself to look where I was going. The trail was too tenuous for me to get distracted by silly things like what was actually around me.

One step. Two. On the third step, I stumbled, nearly tripping over the edge of the pool, and had to dare a glance down in order to recover my balance. I almost lost the trail after that, and had to stop again, closing my eyes and breathing as deeply as I could. The smell of blood had been impossible to miss when we opened the door because it had been trapped. Now, with the air circulating in from the hall, it was getting fainter. I needed to keep moving, or I was never going to find it at all.

Three more steps carried me to the wall. It was covered by a complex tapestry of interwoven fishnets, ropes, and sea-stained lengths of fabric, all studded with shells and interesting pieces of driftwood. There was blood trapped in the fiber, places where the weaver’s fingers had bled in the process of tying knots or securing shells; the image of a dark-haired Merrow boy formed behind my eyes, and was just as quickly filed away. I’d know Peter if I saw him now, but that wasn’t the blood I’d followed into the room.

Shutting out the traces of blood in the tapestry only took a few seconds. My own magic was rising around me again. I borrowed strength from its familiarity, letting it wash away everything but the blood before I knelt and pulled the base of the tapestry away from the wall.

A silver needle glittered among the bottom loops of fishnet, obviously snagged there by mistake. It was practically invisible among all the things woven into the netting. If there hadn’t been time for a full search of the room, Rayseline wouldn’t even have realized that it was missing.

“Here,” I said. The bottom inch of the needle was darker than the rest. I didn’t need magic to tell me it was covered with dried blood. Gingerly, I grasped the opposite end and began working it free of the tapestry. “I found something.”

“What is it?” This time, no amount of restraining was going to keep Dianda out of the room. She strode toward me, practically vibrating with the need to know what I’d found. “How did my people miss it?”

“They didn’t smell the blood.” I held up the needle. “I wouldn’t touch this if I were you. This is a blood magic charm.”

“Intended to do what?”

“I’m not sure.” I brought the needle to my nose, sniffing cautiously. “It smells a little bit like elf-shot, but it’s not quite elf-shot. I’m going to need to take this to an alchemist friend of mine; he’ll be able to tell us more.”

Dianda’s expression darkened. “If you think I’m going to let you swim out of here with that—”

“I’m exactly right,” I finished. “Dianda, I’m trying to save your sons. We know Rayseline was involved, and we know this is blood magic. There’s no way she brewed this on her own. That means we need to find out who did brew it, and the best way to do that is to learn exactly what it is. Walther will be able to do that. You’ve trusted me this far. Is there anything to gain in taking that trust away from me now?”

Dianda’s eyes flicked from my face to the needle and back. Finally, she said, “Helmi will fetch you a water-tight bottle to transport it back to the surface. You have until the morning tide rolls in twice to tell me who took my children. Do you understand?”

“Yes,” I said. I wanted more than that—I wanted her to promise we wouldn’t be going to war—but I knew better than to demand. Her children were missing. I was lucky she was still being as reasonable as she was.

“Good.” Dianda’s shoulders drooped. “I . . . is there anything else we can show you? Anything at all?”

I took a deep breath. “Honestly, I don’t know. I’m not familiar enough with the way your knowes are constructed. How about you take me on a tour of the boys’ favorite spots, and we’ll see if anything else jumps out at me?” I glanced at the needle. “After Helmi brings the bottle, that is. I’ve already jabbed one dubiously enchanted pin into my leg tonight, and since that ended with me growing fins, I’d rather not do it again.”

“All right,” said Dianda. She rubbed her face with one hand, looking overwhelmingly tired. “A tour it is.”

“And an escort to the surface afterward, if you don’t mind. I don’t think I can find the way back on my own, and this,” I waved a still-webbed hand, indicating my body, “isn’t going to last forever. I won’t be very much use to you if I drown when the Luidaeg’s spell wears off.”