Kira watched the two Partials—the two other Partials, she reminded herself—and wondered. What would happen when they reached Chicago? Would it be infested with Watchdogs, or dragons, or something even worse? Would Afa betray them, or would Heron? No matter how much they bantered, Heron always stayed aloof, always stayed an observer more than a participant. What was she observing? Who was she observing for?

Kira slept against a tree, her back to the fire, her hands on her rifle. In the morning they tested the solar panels, and the radio repeater fired up instantly. Afa had done it all without a hitch. Samm nodded, and though he didn’t say it, Kira got the distinct impression that he was impressed—surprised, almost certainly, but still impressed. Kira patted Afa on the back. “Good job.”

“The Zobles are extremely durable,” he said, though his voice seemed off. “They use a mad cow matrix around doped silicon crystals to increase efficiency.” Kira nodded, unsure how much of his response had been meaningful science, and how much was pure gibberish. His intelligent persona was mingling with his childlike one, which might be good or bad in the long run. Kira was worried that whatever mental scaffolding allowed him to function was starting to break down.

“Let’s test the radio,” she said. He complied, flipping it on and turning the knob carefully, falling into the easy patterns of a technical task he’d done countless times before. He turned, and listened, and turned, and listened, until finally he hit on a man-made—or Partial-made—signal. Kira leaned in closely while Afa fine-tuned the connection.

“. . . retreated. Our sources on the island say it’s only . . .”

“Partials,” said Heron.

“Can you tell which ones?” asked Kira. Afa shushed them, his head cocked toward the speakers.

“. . . killing a new one every day.”

“Northerners,” said Heron. “Trimble’s people, from B Company.”

“What are they talking about?” asked Kira.

Heron narrowed her eyes. “Probably the expiration date.”

“We need to find Marcus,” said Kira, and gently pulled Afa away from the tuning dial. She and Marcus had set up a rotating schedule of frequencies back when they’d been communicating during the invasion, hoping it would make them harder to listen in on. She added the days in her head, calculating which frequency they’d be using today, and hoped he was still listening. She turned the dial and clicked on the microphone. “Flathead, this is Phillips, are you there? Over.” She clicked off the mic and waited for a response.

Heron smirked dismissively. “Flathead and Phillips?”

“That was his nickname in school,” said Kira. “What can I say? He had a kind of a flat head. I started using it to call him couple of weeks ago, because I knew he’d know it was for him, and nobody else would.” She shrugged. “Just another layer of paranoid security. Phillips just seemed like the natural counterpart.”