Kira nodded. “The ParaGen headquarters were in Denver. I’m not really up on my old-world geography, but I’m pretty sure that’s not close.”

“It’s not,” said Heron, “and the road to get there is, by any estimation, hell.”

“How horrible could it be?” asked Kira, gesturing around. “We’ve made it through this, didn’t we? Is Denver any worse?”

“We honestly don’t know about Denver,” said Samm, glancing at Heron, “but most of the Midwest is virtually uncrossable, thanks to Houston. It was the biggest oil and gas refinery in the world at the time of the Break, and without anyone to keep it operating properly, it started to fall apart. Eventually it lit on fire—a lightning strike, maybe, we don’t know for sure—and it’s still burning ten years later, creating a cloud of toxic fumes a thousand miles wide. The entire Midwest is a toxic wasteland, everywhere those gases have been blown to by the Gulf wind.”

Kira raised her eyebrow. “And this is your plan?”

Samm’s face remained stony. “I wasn’t intending to enjoy it, but if it’s the only way, it’s the only way.”

“It’s not the only way,” said Heron. “We could call in Dr. Morgan right now and end this entire thing—the search, the war, everything. We know now that even if she doesn’t know everything about RM and expiration, she knows more than she’s let on, and the information we have might be enough for her to come up with a plan to cure us. And we wouldn’t have to cross this nightmare wasteland to do it.”

“She’ll kill Afa,” said Kira.

“Probably.”

“She’ll kill everybody,” said Kira, feeling an edge of steel in her voice. “She wants to solve the expiration date—”

“That’s exactly my point,” said Heron.

“—but I’m trying to solve them both,” said Kira. “Expiration and RM. They’re connected through the Partials, and through ParaGen, and if we can find the ParaGen records, we can find the answers we need. If we give up and side with Morgan, the humans die.”

“The humans will live,” said Heron, “because Morgan will stop killing them looking for you.”

“So they’ll die in a few decades,” said Kira, “but they’ll still die. RM won’t be cured, and they won’t be able to reproduce, and the human race will go extinct.”

“Did it ever occur to you that maybe it’s time for them to go extinct?” Heron asked. Kira felt like she’d been punched in the face. “Maybe humans are just done,” said Heron, “and it’s time for the Partials to inherit the Earth.”

Kira’s voice was a hiss. “I can’t believe you would say that.”

“That’s because you still think you’re one of them,” said Heron.