“Don’t change the subject. Especially not to that subject.”

The older man’s expression held, though. He looked back and forth at Skyler’s eyes, as if seeking his answers there. “You two should hash this out, Skyler. It’s unhealthy.”

“I’m here if she wants to talk.”

“Bullshit,” Karl said, his voice even. “Every time she comes down you either have Ana at your side, or me. Plus some excuse locked and loaded in case you might be forced into any conversation other than the business at hand.”

“And every time I try to get out of here, to go do the work we all know needs to be done, she finds some critical project that simply must be top priority. Or she simply writes it off as too risky. You all do.”

Whatever Karl had been about to say, he swallowed it, and visibly calmed himself. “You’re both acting like children.”

“I’ve been cordial. I’ve done everything asked of me.”

“I know,” Karl said. “I know. I just wish you two would put that business with Gabriel behind you.”

“That’s not even the issue anymore. At least it’s only part of it. Karl, we’ve squandered a lot of time. The calendar is no longer on our side. Digging out this room shouldn’t even have been on our radar. It’s a diversion.”

Karl fell silent.

Skyler went on. “I never thought I’d see it happen, but all these scientists, Tania chief among them, seem terrified of risks, of the unknown. The camp needs the tools required for survival, granted, but we’ve done everything we can without expanding the aura. And all the while the clock ticks.”

He took a breath. When Karl said nothing Skyler went on. “Those towers vacated the camp for a reason. We all know it. That thing, whatever the hell it is, out there in the rainforest, is there for some purpose. It must be. Karl, dammit, we need to figure out what the hell is going on here before the Builders throw everything out of whack again. Zane is stable. The camp is operating smoothly. Our last two trades with Blackfield came off without a hitch. And …”

“… time is running out.” Karl finished for him.

“Exactly. Yes.”

Karl stared into the abyss for a long time. Thick with the smell of soil and rock, the air felt heavy even compared to Belém’s humid standards. “Maybe you should just go then,” he said, finally. Then he turned toward Skyler and gripped his shoulder. “You’re right. Tania will find reasons to keep you here as long as possible, simply because she doesn’t want to lose you.”

“I’m useful, sure, but not invaluable. We have other immunes now—”

“She doesn’t want to lose you, Skyler. Don’t act like you don’t know that. That business with Gabriel, the decisions she was forced to make, devastated her.”

“That may be so, but no one forced her to lie to me about it.”

Impatience flashed on Karl’s face. “Is it so goddamn hard to understand? She was consumed with guilt and saw a way out with just one little white lie. I would have done the same damn thing. But then you caught her in it and had to make a big goddamn stink about it. Did you know she almost quit after that? She wanted to, wanted to run off to Black Level and hide in a cloud of research again.”

Skyler hadn’t known. “Why didn’t she?”

“Talked her out of it. Zane and Tim, I mean, though I would have been happy to help persuade her. Put yourself in her shoes, Skyler. Brilliant scientist, the favorite son—if you’ll pardon the expression—of Mr. Platz. She never asked to be the leader, to make decisions that had people’s lives hanging in the balance. All she thought she had to do was tell Neil the specifics of the new Builder ship, and then let him take the reins like he always did before. Except it didn’t work out that way. Neil finally lost a battle and out of every possible candidate he trusted her with carrying out his plan. I think if Neil Platz earned one thing in his life it’s our trust in his judgment of people. He chose you, too, you know. And me.”

A picture came to Skyler’s mind. The research room on Black Level, where they’d shared a bit of food and drink while they discussed Neil’s plan. For all her drive and bravery, he’d seen the terror deep in her eyes. He’d tasted it, when she kissed him moments earlier as thanks for coming to help. He had undertaken that journey with a single-minded sense of purpose, and even left his friends behind in order to seek out Tania. For all the reasons he’d used to justify the race to find her, he knew deep down the truth of it: He’d wanted to be with her. The oldest, dumbest reason in the book. Who’s the liar? What excuse did I give Prumble, or Sam? Something about seeing Neil’s plan through, about Tania being the key to it all. Bollocks.

“Maybe some time away,” Karl said, “would do you both some good. Prep your aircraft, get your crew ready, and find out where those towers went. I’ll explain to Tania and the others. She’s more likely to come around to the idea you’re just tracking the other three, instead of tackling those demons in the forest.”

Skyler found himself nodding, even though he felt trapped between two choices. Part of him wanted to rush to Tania as he had in Darwin. Apologize, do whatever it took to rewind back to those first days after leaving the city and its Elevator behind.

That was impossible now, though. He knew it. The rift between them had grown too large, and of course there was Ana.

Wild, insatiable Ana.

She’d shared his bed a hundred times now and seemed to grow more eager each time. More than that, she loved him. She’d said it often enough. He’d even repeated the words in the darkness when they lay together, their bodies entwined in the heady sweat of afterglow.

Skyler shook his head to clear the memories. Karl took this as refusal and started to argue, before Skyler silenced him with a raised hand. “We’ll take off tomorrow at dawn.”

“Okay. Good.”

“And Karl? Thanks, friend. For speaking your mind.”

Karl clapped him on the shoulder. “I’ll talk to Tania after you’ve left. Find our towers, Skyler.”

La Gaza Ladra’s engines roared to life the instant the sun peaked above the canopy east of camp.

Skyler let Ana handle the preflight. He’d walked her through it at least fifteen times already, and on the last flight she’d handled it with only minimal supervision.

He glanced back through the open cockpit door. In the rear compartment, Vanessa and Pablo double-checked the gear. The clean, tasteful interior of the luxury passenger cabin had been abandoned long ago, in the first weeks of recovering the vessel. The cosmetic back wall had been unceremoniously removed, along with the widescreen display and wet bar attached to it, though not until after a raucous movie night. Behind the cabin was a cargo compartment equal in width and with a floor a meter lower. Removable panels within gave access to a crawl space below the passenger cabin, ostensibly for maintenance of the wiring and ventilation systems that supported the area. To Skyler’s eye, there was a clear secondary purpose for smuggling.

Two doors on either side of the aircraft’s belly provided external access to the cargo space. The design allowed for easy stowage of luggage and small items, but was next to useless for recovery of large items. Skyler felt a bond to the aircraft already, but he knew it would have to be replaced with something more practical at the earliest convenience.

“Tower, this is the Magpie. We’re heading out,” Ana said into her oversized headset. Though everyone liked the ship’s full name, the easier slang version had become more commonly used.

Of course, there were no other planes, no air traffic to manage, but Skyler had insisted the traditions of tower courtesy be maintained, even if informal.

“Magpie, this is the so-called tower. Safe travels, and keep me posted on what you find as long as you can.”

“Count on it,” Ana said. She flashed Skyler a thumbs-up, an unwitting echo of Angus’s signature gesture.

She’s older than he was, Skyler realized suddenly, further eroding his initial misgivings about her age.

“The stick is yours,” the girl said, which got a quick raise of the eyebrows at the innuendo from Skyler.

“Thanks,” he said. “If you’re good I’ll let you fiddle with it later.”

Ana scoffed and rolled her eyes, but not without throwing a small smirk his way.

“Buckle up back there!” Skyler shouted toward the rear.

A few seconds later Pablo called out, “We’re ready!”

On the central screen in front of Skyler, a flashing icon reminded him that a flight plan still hadn’t been entered. He’d fretted over this choice for months, after carefully entering in the four options now presented to him. Four paths traced out from base camp, carved by the tower groups that went haywire during the fight with Gabriel.

One group, of course, went northeast to encircle the crashed Builder ship. Protecting it, apparently, though Skyler also held the theory that they were protecting everything else from what lay within their ring. He wasn’t interested in this group, however. Their location was known, as was the danger they surrounded.

That left three other choices.

One took a path almost to the same location. North by northeast, through the rainforest and then beyond. They’d flown along its trail as far as the coast once, and lost track of it at the waterline. Either the towers had sunk into the ocean, or they’d crossed it. Some of it, anyway. At least the path ran straight, which meant they could follow it on a map.

Yet another group left the camp heading due east. A few weeks ago they’d followed the trail for a hundred kilometers or so before turning back to base. An interesting discovery had been made: The path wasn’t straight, as it had appeared from the ground. Looking at it from altitude, they could see that it had a slight curve to it.

The same was true of the last group’s route. The group had gone northwest, carving a line right through the city and leaving a path of destruction in its wake, like a tornado with no collateral damage. The curve of its path was almost too subtle to detect; it was only when he’d taken the aircraft up to three thousand meters on a clear day that the gentle arc to the line could be seen.

Curvature worried Skyler. On the surface it would still be fairly trivial to trace on a globe, but they had no evidence that the paths would always follow the same trajectory to their end. What if the curved paths changed directions, or straightened out? What if the one straight path started to curve later along its route? If they could indeed cross water, and the direction change happened out in the ocean, all bets were off.

There was no way to know except to follow one.

“Three paths diverged …,” Skyler said to himself.

Ana, he realized, had been watching him as he stared at the choices on the screen, a bemused smirk on her face. “I vote for whichever takes us the farthest away,” she said softly.

“No way to know that for sure. How about the one we know hits the ocean?”

She cracked a grin.

Skyler grimaced. He liked the idea, too, but if the path was truly straight it wouldn’t cross land again until it reached the Azores, an island group in the North Atlantic. That was near the edge of the Magpie’s range. If they couldn’t find a place to recharge the caps there, or a replacement aircraft, they could wind up marooned.

He looked at Ana and saw simple determination in her eyes. Just go for it, they said. There were worse fates, he decided, than being stuck on an island with her, Vanessa, and Pablo. None, he suspected, would mind terribly.

“It’s settled then. North by northeast.”

A path of destruction along the ground made the need for navigation pointless at first, but that didn’t stop Skyler from keeping Ana busy. He quizzed her on various parts of the instrumentation and had her supply regular updates on their capacitor status, even though the Magpie’s computers would alert him to anything that jeopardized the flight plan.

The young woman took to the tasks with some difficulty. It had become obvious to Skyler since they’d first flown the bird on a mission that she learned through example and hands-on activity, not through studying flight manuals or maps as Vanessa did. The older immune was already able to handle the craft with minimal help, and Skyler suspected with only a few more hours of flight time she’d be ready to handle the duty solo. Not so with Ana. He’d given the two women equal time in the pilot’s chair—mostly so as not to show favoritism—but Ana simply didn’t have the deftness, the patience, that Vanessa did. Still, even if she ended up being unsuitable as a co-pilot, the knowledge she absorbed wouldn’t hurt.

The straight gouge left behind by the towers ran for a hundred kilometers through rainforest, a town, a small city, and then still more rainforest. The path ran roughly parallel to the Rio Pará until the mouth of the waterway began to widen. Ahead, the Atlantic Ocean stretched from horizon to horizon, and Skyler began to gain altitude as they crossed over the body of water. According to the flight computer, they would make the Azores island group with just 2 percent charge left in the ultracaps, and Skyler wanted to be able to glide a long way if the need arose. He’d also marked backup landing locations in the system for each leg of the trip. A return to Brazil in the first third, a landing in the Cape Verde islands off Africa’s western coast in the middle leg, and beyond that the Azores were their only choice, really.

At cruising altitude, Skyler tapped the comm. “Belém, this is Magpie. We’re about to leave radio range. Following the northeastern tower group.”

“I hear you, Magpie,” Karl said. “Somehow I thought you’d pick that one.”