On the third afternoon since our quarantine, birdsong echoes down the tunnel. Their high chirps convey a freedom that electrifies me. In all my study for my chosen focus of aehrixi, the group of animals that fly, birds have always fascinated me the most. They're independent, graceful, and free-willed, but no matter where they fly, they always find their way back home.

In Erreliah, I used to wander for hours through the menagerie's aviary. Nostalgia creeps up in my throat, but I swallow it. Right now, despite its surrounding darkness, my city shines bright in a cavern far below me, as though the architects stole a million stars and sprinkled them through the streets. My hand clutches my charm. I'll be home eventually. Once we make it topside, I can get directions and make the trek back east, past Karsix and on to home.

Right now, though, the birdsong calls to me, urging me to burst into the open and leave the darkness and death behind. The first rays of sunlight filter through the mouth of the tunnel. Before, with Sean's lantern, every image was yellowed and fuzzed. Now, in the white, natural light, I can finally see. There's the glitter of the tunnel walls' variegated granite. There's the dirt caked on my arms, the pebbles strewn across the dry, dusty floor, the shimmer of water as a tiny stream threads into a crack in the rock. The blue sky shines like I've never seen before, filling the entire cave mouth. I rush past Sean and into the open air.

The cutting cold snaps my enthusiasm. Wind tears at my hair, greedy fingers combing, tossing, tangling the long, dark strands. Snow and grey grass scatter the ten square feet of flat land in front of us, then drop away with the ground into a rocky, sixty-degree slope. One barren, snow-dusted tree thrusts through the earth like a skeleton grasping at the sky. Thankfully, it's early winter yet, the snow accumulation not having reached the several feet-high mounds that reckless travelers die among.

Opposite us, thirty-thousand feet tall mountains jut against every inch of the horizon. All three times I've seen them, something hollow has rattled within me, an unsettled quiver at my core as my brain struggles to comprehend their monstrous size and strange beauty. The behemoths simultaneously command attraction and primal fear. They force me to realize just how insignificant I am in comparison.

You mortals keep on scurrying about your frivolous lives, the mountain wind hisses. We have been here from the beginning and will be here until the end.

Sean catches up to me. His eyes close, nostrils flaring as he breathes in the crisp air. He looks oddly content standing there, shoulders relaxed, sharp features momentarily softened.

Despite the towering mountains and bitter wind, there's something calming about being out in the open, where no harsh human monuments litter the landscape.

Wait.

My eyes sweep the area, panic mounting. No, no, no. "Sean? We have a problem."

His eyes snap open. "What?"

I swipe my hand toward the barren plateau. "Where in the world is the trading post?"

"It—it's right here." He rakes a hand through his hair, searching. "It's supposed to be right here."

"It's not."

"They must have moved it—"

"Moved it?" My satchel hits the ground with a thud. "Sean, this place is too small for a building, let alone a whole post! Where have you brought us?"

"It was the map, the map must have been wrong—"

"Or maybe your memory's not as great as you think it is."

"Riveirre, I have a nearly perfect memory. It's not like I just"—his hand gestures in frustrated circles—"forgot!" He shakes his head, shoving his hands into his pockets. "It had to be the map."

There's a strange frenzy to his movements that makes me feel bad for him and uncomfortable at the same time. I bite my lip, glancing away. He's not going to admit to forgetting, and there's nothing to be gained by forcing him to. "Well, whatever it was, we're lost now. So what's our next move?"

He paces. "It's simple. We head back the way we came and take the other tunnel."

"That's a three-day trip. And that doesn't include making it all the way through the other tunnel and up to the post. I'm almost out of rations, Sean." I turn to face him. "Aren't you?"

His pace falters for a moment. Then he spins on his heel, talking over his shoulder. "Get more of those mushrooms."

"I'm not some sort of presto food dispenser! Those don't grow this close topside. I might be able to harvest some edibles from the chamber we quarantined in, but again, that's three days away."

He turns back toward me, but his gaze is on his steps. "Humans can survive for three weeks without food."

"Depends on the person, and that's not considering energy expenditure and metabolism. Or the fact that your muscles start cannibalizing themselves after a while. Even allowing that we make it back to the quarantine chamber, you know what humans can't survive, Sean? The Blistering Death, and we can't be sure no one's traveling these tunnels behind us. I don't want to meet up with them halfway."

He skids to a stop. "Then what do you want to do, Riveirre? Because so far, you've done nothing but shoot down my ideas."

"I..." What should have been a sentence trails off into nothingness. The mountains stare down at me, knowing I don't have an answer.

"Haven't actually thought about it yet?" he finishes for me, brow raised.

"No! I—" The wind splays my hair into my face. Frustrated and needing something to do with my hands, I twist it into a bun. "I'm getting there. Give me a minute."

Sean's jaw clenches, and he goes back to pacing. I lean against the skeleton tree, and a crow caws in the branches above.

I know it's irrational, but my thoughts keep circling back to my original goal. "I'd like to go back to Erreliah," I tell him. "We could travel overland—"

Sean scoffs. "Whatever you'd 'like,' Riveirre, that's not a plan. Even if we got unreasonably lucky and found a way there, what do you expect them to do? Welcome two plague survivors with open arms? They'll be checking everyone's passports at the cavern entrances. And since yours is marked 'Karsix'..." He mimes a patrolman firing a crossbow.

I throw my hands up. "What then? You want to winter in some topside, backwards hovel of a town? How would we even find one?"

Only after the words come out do I remember the rumor that those 'backwards hovels' are where he grew up. But what I said is true all the same. They're farmers. They can't spell science, and I seriously doubt their ability to differentiate between a laboratory beaker and a wildflower vase.

"Beats getting shot." He pulls one of the chains out of his pocket, pops the device's lid, and studies its face. "You got a better idea?"

My eyes search the imposing, cold slopes of the mountains for answers I know I won't like. Danger waits in the tunnels. Death waits in Erreliah.

Wintering topside is our only option.

A flash of movement interrupts my thoughts. In the valley far below, a colorful contingent of carts, horses, and humans roll among the pine hills. "What is that?"

Not bothering to look, he nods in mock appreciation. "Nice change of subject."

"Seriously, Sean. What is that?"