“I just need to stabilize the hole between the universes. Make it more reliable. I’ve sustained smaller tears in the past, but they all had this . . . unfortunate side effect. The two worlds bleeding together in uncontrollable ways.”

“Unfortunate side effect?” Simone laughed. “We were kilometers away from Siegen, and still we saw these . . . these rifts. Monsters crawling through the forests. If they can manage to get through small tears, I’d hate to see what a larger hole might bring.”

“I can fix it, I swear—”

“And if the monsters are after you, how is it safe for you to call on them at all? If that energy can corrupt the Germans, how long before it corrupts you too?”

“I can still control it, in small doses.” Liam’s voice took on a fervent edge. His skin had a grayish cast like wet clay, with bruised crescents lurking under his eyes. “Once I can stabilize a rift, I’ll be fully in charge.”

“M-maybe we can figure out how to do this without the book.” Phillip worried his fingers together like he was tapping out a code. “There’s gotta be a way to stabilize it on our own.”

“Could be.” Liam dragged his gaze back toward the group. “Harmonic frequencies open the rifts. I can open a small one on my own, but for a bigger source of energy, I’d need a way to lock that opening in place.”

Phillip gave him a crooked grin. “Well, you’re speakin’ my language.”

Simone threw her hands up with a groan. “Just what you two needed—a peer group.”

“You need something that can cycle the frequencies enough that they stabilize themselves,” Phillip said. “So you don’t have to do it for them.”

“Yes. Exactly!” Liam exhaled a deep, satisfied sigh. “Someone gets it.”

“Well, I don’t know what some old manuscript’s gonna tell you, but I’ve got something that might help.” Phillip reached down for his boots and began to ease open the heel of one shoe.

“What are you doing?” Simone cried. “That is for our mission—”

“Our mission is stopping the Third Reich, isn’t it?” Phillip plucked out a coiled, multipronged device. “I’ve been tinkering with this—it’s like a frequency jammer, but with a more sophisticated routing pattern, multimodal scattering . . . The goal is to fold signals on top of themselves so the Nazis don’t even realize, until it’s too late, that the signals aren’t syncing up. It’s not part of our official mission, but—”

“Our official mission is none of their business,” Simone said.

“You’re setting up secure two-way radio comms, aren’t you?” Liam asked. “Kinda obvious now that I think about it.”

Simone’s headache blossomed so quickly she was sure she’d popped a blood vessel. “Don’t you dare breathe a word—”