“Thanks to Merit,” she said, “we’ve made quite a bit of progress.”

Hope made my heart beat faster. “You found something in the notes?”

“We did,” Mallory said. “Kind of. So, the notes are basically ramblings, which is probably not surprising given how they were ordered around the room. It looks like tidbits of spells she was interested in, ideas for projects, stuff like that. It was basically a really obsessive bulletin board. Together, the pieces don’t make much sense. So you have to consider them individually. And individually, they didn’t make much sense, either. Until I got to this.”

She offered me the piece of paper. It was a photocopy of what looked like a book or journal page. The top half of the page was filled with handwritten words in the small script of gilded medieval manuscripts. The bottom half of the page bore sketches drawn in a thin, scraggly line. What looked like a globe near what looked like a star, with two-dimensional renderings of humans.

“It looks old,” I said. “But not particularly familiar.”

“Nor to me,” she said. “Especially the completely whacked-out language. But I did a little sleuthing. It’s a page from the Danzig Manuscript.”

“You’re kidding,” I said, but gave the page another look.

“And what is the Danzig Manuscript?” Luc asked.

I hadn’t actually seen the Danzig Manuscript, but I knew enough about it. “A book written in the seventeenth century,” I said. “Drawings of plants and animals that didn’t exist and writings that weren’t in any identifiable language.” Mallory was right—the letter forms weren’t entirely clear on this photocopied page, but it wasn’t a Latin alphabet, or Cyrillic, or any alphabet I recognized.

“There are a few dozen theories on what the book’s supposed to mean,” I said. “Whether it was encoded or encrypted, the last writing in a lost language, the ramblings of a madman, a very old practical joke.”

“And Ethan happens to have a facsimile of the book in his magnificent library.”

Mallory reached out a hand to Catcher, who offered her a large, dark leather book. She opened the book to the page she’d marked with a ribbon. It matched the page from Sorcha’s office exactly.

Ethan looked at the book over my shoulder. “And no one has conclusively determined what it means?”

“Not in four hundred years,” I said.

Mallory smiled slyly. “Well, not until tonight.”

I looked up, stared at her. “What?”

“I translated the Danzig Manuscript.”

“You’re joking.”

Her grin was huge, proud. “I am not joking. It took me a good hour to figure out the trick,” she said with a wink. “But I have skills most academics lack.”

“Skills?” I asked, then looked down at the page again.

“Abracadabra,” Mallory said, and drew a symbol in the air above the text.

Bright magic spilled into the air, and with it the slightly musty scent of old books, of dark and cool library aisles. The letter forms stretched and shifted like they were animated, then reassembled themselves into Latin letter forms and English.

I flipped to the next page, then the next. All of them had been translated by Mallory’s magic.

“Holy shit, Mallory.” I looked up at her. “You translated the Danzig Manuscript.”

“I know, right?” She blew on her fingernails, buffed them on her shirt. “I’m a badass. Fortunately, the magic is contained in the manuscript’s words, not the pages. That’s why this little translation works on Ethan’s facsimile.”

“So what is it?” Lindsey asked. “And what’s the significance here?”

“As it turns out, the Danzig Manuscript isn’t a joke or ramblings, although it was encrypted. It’s a grimoire.”

“A spell book?” I asked.

Mallory nodded. “Of a sorcerer named, I kid you not, Portnoy the Ugly. The words are in English, but they’re in Portnoy’s magical shorthand, which is taking time to translate. We started with the page you found in Sorcha’s office.”

She pointed to the globe, the circle of crudely drawn humans. “The text describes a group of humans with powerful emotions. Strong emotions that are cast off into the world.” She traced a finger to the starlike figure. “Magic unites those emotions, gives them a spark. A creature is born from that collective spirit. It is alive, and it is sentient.”

She lifted her gaze to us. “It’s called an Egregore. That’s whose voice we hear.”

The room went silent.

“How?” Ethan said.

“Sorcha’s Trojan horse,” Mallory said. “The magic that didn’t dissipate after Towerline.”

Catcher leaned forward. “Think about the emotions people were feeling around Towerline when the battle occurred. People were freaked out by the fight, the supernaturals, the river, the possibility of the building falling over. The city was in crisis, and that was in addition to all the other things they normally worry about. All that fear, anger, and worry was gathered together by Sorcha’s magic.”

“It was distilled,” Mallory said. “Just like the scent of that magic is the distilled essence of Chicago.”

“We’re hearing the Egregore,” Ethan quietly said, studying the picture, then lifting his gaze to Mallory. “Magic creating life?”

“A form of it, anyway.”

“And why would she do all this?” Ethan asked. “Create this collective magic? Work to create this Egregore? To foster the delusions? To use them as a weapon?”

“I think the delusions are a side effect,” Catcher said. “There were thousands of people near Towerline, but the delusions have been relatively rare, sporadic, and geographically focused. That’s probably because Sorcha’s magic didn’t disseminate evenly.”

“The fact that she’s never been trained hurts her,” Mallory said, nodding. “She’s got skills, sure. But it’s raw power, untrained.”

“And that’s much more dangerous,” Ethan said. “Not to mention the fact that she’s narcissistic and unpredictable. She has changed the weather. Endangered the lives of millions. Brought the city to a standstill because she could.” He glanced at Mallory. “Because you didn’t let her have her way at Towerline.”

“She’s acting like a hormonal teenager,” Lindsey said. “She is basically the worst Sweet Valley High novel ever written.”

“Based on what we know about her,” Luc said, “that’s how she operated her entire life. She gets what she wants, usually because someone paid for it.”

I nodded. “She doesn’t even fight her own battles. She used alchemy to control sups so they could do the fighting for her. She wants to win the war, but she doesn’t want to fight it. She wants power with impunity.”

“She wants a weapon,” Catcher concluded, nodding at me. “Just like we were supposed to be.”

“The Egregore is sentient,” I said. “If she can control it, it can fight us on her behalf.”

Mallory nodded. “We think that’s where she’s going, too.” She gestured to the book. “But we haven’t had time to get further in the book, so we don’t know what she’ll try next, or how the weather relates to it.”

“Another question,” I said. “If the Egregore is going to be her weapon, why does she want us? Why the ultimatum?”

“Revenge,” Ethan said, and the word hung in the air, heavy and dangerous.

“I’m sure that’s part of it,” Mallory said. “But that can’t be all of it. She’s creating a spectacle, sure. But she’s also giving us a chance to prepare, to be ready. To be armed. We’re missing something. Something involving the Egregore and us together. I just can’t see what it is. I either need more time to work through the Danzig”—she turned to Catcher—“or I need to go to the source.”

Catcher glared back. “Don’t even think what you’re thinking. Jumping into her arms won’t change anything.”