His ax went wobbly, due to its weight. He drew it back up and held it with both hands.

The fox quivered and hopped back half a step. It snapped its jaws, spraying yellow-tinged spittle in every direction. Then it made up its mind, turned sharply, and dashed away. It disappeared through the fog in an instant, and the sound of its small feet—its little claws clicking against pebbles—lingered only a moment longer.

All three boys exhaled hard and let their weapons fall to their sides.

“I’m glad we didn’t have to kill it,” Zeke confessed.

Houjin said, “I don’t know. It isn’t happy being alive in here.”

This time, Rector agreed with Houjin. “Should’ve just smashed its head in. Would’ve done it a kindness.”

But Zeke still sagged, looking unhappy behind his visor. “I feel sorry for it. I wish we could’ve caught it, maybe let it go outside the wall.”

“So it could go bite other foxes, and make them sick, too?” Houjin swung his bar up over his shoulder so it rested against his neck.

Zeke did likewise with his ax, and sighed. “Maybe if it got some fresh air, some regular air, it’d get better.”

They still whispered, though their caution evaporated somewhat in the wake of the fox’s disappearance. Rector still brought up the rear, watching backwards to make sure no one followed them, and praying that Houjin and Zeke would see anyone up ahead. It was odd, feeling so alone but knowing that they weren’t—that the city crawled with sick and dying things, and dead things that hunted regardless.

Rector surveyed the wall, too, but it stayed firm and showed no signs of holes, or even cracks. There were no breaches big enough to let anything person-sized (or even fox-sized, or rat-sized) in or out. He clung to it, oddly comforted by its epic reliability.

He said, “I thought maybe that fox was a good sign.”

Houjin looked back at him. His face was a masked shadow. “Why?”

“You saw it. It hadn’t been inside for very long. Makes me wonder if we’re close to the entrance, or exit.”

“But you saw it run off,” Zeke said. “Those things move pretty fast. It could’ve run pretty far.”

Huey paused, and the two boys who followed him paused, too. “What if we’re going about this the wrong way?”

“Everything feels like the wrong way, down here,” Rector said. He was getting thirsty, and he was also getting the very smothered feeling of spending too long in a gas mask. He wanted to get inside, someplace where the air was clean. He was running out of patience, and he didn’t want to admit it. It grieved him to think that the wall held several square miles of space, which meant that there was still a whole lot of territory to check before he could report to Yaozu that he’d done his job.

“That’s not what I mean. What if the hole isn’t in the wall—what if the hole is underground? Say one of the tunnels collapsed and left a spot that stretched beyond the wall, to someplace outside. What if things are getting inside that way?”

Rector snorted with exasperation. “Or what if they’re dropping from the sky, hitching rides on crows or dirigibles?”

“Don’t be like that,” Houjin groused back at him.

“Look, Yaozu told me to check the wall. He didn’t tell me to dig through every underground tunnel, pit, shaft, or cave. One thing at a time, all right? Let’s rule out the wall, and then move on to other ideas.”

Huey conceded, “That’s not the most unreasonable thing you’ve ever said.”

“God forbid you admit I had another good idea.”

“It’s not a good idea. It’s a plan someone else gave you, and you’re sticking to it because it’s the easiest thing to do.”

Zeke rolled his eyes and started walking along the wall. “Can’t you two get along for ten whole minutes? I don’t know what your problem is.”

“This guy, he’s the problem,” Rector said.

Huey retorted with a “Shut up.”

This once, Rector did so—but not because of the command. It was his turn to hear something, out in the fog. “Guys? What’s that?”

From back in the fog somewhere in front of them, a voice called back. “Silly boys. You’re making enough noise to wake the dead. Or call ’em to supper.”

Princess Angeline stepped forward out of the filthy mist, a close-fitting mask covering her face—though her eyes showed, and her silver hair was left to flop around her shoulders. She wore a pair of canvas pants, and a jacket that was buttoned all the way to the top, stopping just under her throat. Slung around her chest was a bandolier that held a row of small throwing knives.

Houjin perked up immediately. “Miss Angeline!”

“Hey there, fellows. You’re a little far from home, ain’t you?”

Zeke said, “Yes, ma’am, but we’re on a mission.”

“What kind of mission?”

Rector stepped in, since the mission belonged to him. “We’re checking the wall for holes. We think the rotters are getting out, and animals are getting in. We know the men out at King Street have been watching their end of the wall, so we thought we’d start at this end.”

“That’s either brave of you, or dumber than homemade sin.”

“A little of both?” Zeke tried. “We were getting ready to head back to the Vaults. We’re thirsty and hungry, and we haven’t seen anything except for one sick fox.”

“Aw, a fox? That’s a shame. You saw it wandering around up here?”

Houjin said, “Yes, ma’am. We chased it off.”

Angeline put her hands on her hips and cocked her head thoughtfully. “It’s not a bad idea. Not the bit about the fox, but the bit about a hole in the wall. Should’ve thought of it myself, but I’ve been in and out of town a lot. My grandson is getting married out in Tacoma, so I haven’t been around so much.”

“Didn’t know you had a grandson,” Zeke said with a touch of awe.

“I do. But that’s beside the point. You think we have a hole?”

Rector wasn’t stupid enough to mention that it was Yaozu’s theory, and the other two boys kept that particular piece of information quiet as well. He’d been warned that the princess hated the powerful Chinese man who ran most of the Station. And even if Rector hadn’t liked her, he didn’t want to anger a woman who wore that many sharp things attached to her clothes.

So all he said was, “A hole, a crack … something that lets things out, and lets things in.”

Houjin added, “There must be someplace where people see Blight-sick animals more often. Now that I think about it, we really should’ve followed that fox.”

Rubbing at her chin under her mask, Angeline said, “You’d never have caught him. There’s plenty of strange goings-on here in the wall these days, boys, I tell you what—it gets weirder by the day.”

Intrigued, Rector asked, “Why do you say that?” But he did so in a normal speaking voice, and everyone else shushed him. “Sorry! Sorry,” he said much more softly.

“That’s right, boy. Don’t ever forget where you are.” She came in close to the three of them, gathering them around her as if she meant to shield them. “Always keep your voice down low. Always. We can talk between us, but keep it quiet.”

“Yes, ma’am,” Zeke and Houjin said.

Rector nodded, then he said, “I was trying to ask: Did you ever hear of something called an inexplicable?”

She frowned. “Nope. What’s that word mean?”

Houjin told her, and she said, “All right, I’ll remember that. And let me answer your other question, Red,” she said, perhaps misremembering his name, or just having decided to call him that. “Actually, how about I show you, rather than tell you.”

He hemmed and hawed. “Aw, we were just heading back down to the Vaults, like we said.”

“Yes, and I heard you. You’re heading over to the Sizemore House?” she asked Houjin, who bobbed his head.

“Down through the basement, and back to the Fifth Street tracks.”

“Good plan, good plan. I’ll come with you, and on the way, I’ll show you what I mean. It’s only a quick detour.”

“Give us a hint?” asked Zeke.

“Hard to hint, dear boy. Except to say, I’m not sure the rotters are all escaping. Between us … I think something’s killing them.”

Rector did not say that she might be right, and that she’d just hit on part two of Yaozu’s theory.

Duly hushed and thoughtful, the boys followed the princess around the wall another few dozen yards, then marked their place with a small cairn of bricks and rocks. “To remember where we left off,” Houjin said. “We can start here next time.” And then they left the sturdy familiarity of the Seattle wall, venturing once again into the Blight-ravaged blocks of what was once the city proper.

Rector trudged after the princess, and after Zeke and Houjin, in what was becoming a regular lineup.

Bringing up the rear, that was how he preferred it. Let them walk headlong into whatever trouble waited. Let them stir up the monsters, or wake up the ghosts. It’d buy him time to run, if running was called for.

But run to where? He didn’t know what the Sizemore House was, or where it was, or how to find it. Nor could he have found his way back the way he’d come. He hadn’t counted the steps around the wall, or the building fragments falling down to block their paths. He hadn’t counted anything. He’d only counted on Houjin and Zeke knowing what they were doing. That had been a mistake.

They moved in a nervous pack, pausing only to light a lantern when Angeline suggested they ought to. She was right. The wall’s shadow was stretching to catch them, and the setting sun behind it left them straining to see.

Only one light burned, and Angeline carried it. Rector thought about objecting, but then he thought about rotters pouring out of the derelict shops and abandoned houses, and he thought they would surely go for the source of light first and foremost. Fine, let someone else carry it.