CHAPTER 3

Callie and Ashok were floating in the cargo bay as the small drone returned, bearing the key in its manipulator arms. “Just floating there, unharmed, as you predicted,” Callie said. “Think it’s safe to touch?”

Before she could stop him, Ashok gripped it in his manipulators, then tapped the shaft gently with one bare finger of his other hand. “Feels like glass. Cool and smooth. I would avoid touching the in-and-out-of-reality triangles though. You might lose a finger.”

Callie took the key and held it up, watching its teeth dissolve and erupt. “Those Liars were willing to die to protect this. They’ve been guarding it for millennia, probably, passing on the directive to guard it to generations of babies.”

“Let’s see why.” Ashok stroked the greasy-looking crescent he’d strapped to his wrist, and a slit appeared in the air. “Activates just like the short-range teleporter.”

Callie sighed. “Please don’t open holes in space-time on my ship again without asking first.”

“You don’t want to go?”

She sighed again. “Shall, let everyone know Ashok and I are leaving the ship to check something out.”

“Are you taking the canoe?” That was their small boarding-and-landing vessel, currently in the cargo bay.

“No, we’ve got an Axiom toy that opens doors in the air.”

“Better go quick before Elena finds out,” Shall said.

Elena Oh was the ship’s executive officer, doctor-in-training, and the love of Callie’s recent life. She was generally very supportive, but even she had her limits, and Callie thought this might just brush up against them.

Ashok gestured at the tear before them. “Rank has its privileges.”

Callie took a breath, then moved through the slit. It was nothing at all like passing through a wormhole bridge. It was much more like pushing through a curtain made of rotting meat. Even through her spacesuit, something about the texture of the ragged air, pliably giving way against her body, made her shudder.

Ashok followed and the slit sealed up behind him. He looked at the screen on his arm and whistled. “This is… we’re in the same place we were before. Like, coordinates-wise.” He looked around. “Cap, I think we’re in the fourth dimension.”

Callie looked around. Fluted pillars, white walls etched in what she now recognized as the eye-twisting script of the Axiom, a smooth white floor, and that dome overhead, the alien sun a little lower now. “Up, down, side-to-side – I still just count three dimensions, unless you include time, which we’re wasting. Besides, I don’t remember much undergraduate math, but I know the fourth dimension isn’t a place, it’s a dimension of space we can’t perceive.”

“Yes, true – I was being dramatic, but the situation warrants it. We’ve moved from our local space-time into a… not adjacent, exactly, but overlapping? No, that’s wrong too. This thing doesn’t teleport us, at least not to another point in our space-time. It doesn’t make a wormhole. It’s a phase-shifter. The Liars were using them to sneak up on us, ducking in here, then emerging in another place in our usual spatial reality.” He looked around. “I wonder how they control where they come out.” He touched the crescent and another opening appeared, showing their cargo bay. He sealed it up. “Opens in the same place we left from. Good, but boring. Hmm. This looks like the same room I glimpsed through the portals on the station, even though we’re kilometers from that position. I don’t think this place bears any relationship to our spatial coordinates. It’s some kind of pocket universe.”

“A pocket universe with its own sun? Seems a lot more likely we’re in an unknown system.”

Ashok looked at the ceiling and whistled. “Look, there, and over there.” He pointed. A couple of small panels in the immense dome were black. “I think you’re right. I think that dome is a viewscreen, just projecting an image. Maybe that moonscape is where the cultists used to live, or something. I don’t believe there’s really a sun or moon outside.”

“Then what is outside?”

“Um. Possibly… nothing. Literally nothing.”

“I’m not sure that makes any sense,” Callie said.

“Me either, to be totally honest – I’m an engineer, not a theorist. But we’re here, and I don’t think here is a place you can get to in a spaceship. It might not even be a real place, as we understand places. And reality. This could be an Axiom construct, a little extradimensional hideaway created to keep… That.”

He pointed past her. Callie turned, and whistled. There was a vault door set in the wall behind her, an archway of golden metal five meters high and three meters across, with a hole in the center about the height of her head and the size of her fist. She looked down at the still-shifting key. “You think this key opens that door?”

“Occam’s Plasma Grenade.”

“But a lock, and a key, it’s so… old-fashioned. The Axiom could manipulate constants of space-time. Why would they lock something in a vault?”

“A vault hidden in another dimension, with a key that exists in multiple dimensions. Why not? That vault’s not hooked up to any kind of computer system, so it can’t be hacked. I’m guessing the biggest bomb we’ve got wouldn’t put a scratch on it – it’s probably extradimensional too. You can’t pick that lock, unless you have lockpicks that exist in four dimensions, and I don’t. One key, to open one vault, protected by self-destructing zealots. We would never have gotten here with the key if the Axiom hadn’t abandoned that facility, for whatever reason, however many centuries ago, and let their operational security go to shit.” He grinned. “So do we open it?”

“The Benefactor’s message said this station was one of the most dangerous Axiom facilities in the galaxy,” Callie said. “Given some of the things we’ve encountered… that sounds pretty dangerous. The Benefactor told us this station should be destroyed, for the sake of all life in the galaxy. Or it could have been a trick to get the key so the Benefactor could open the vault and get whatever’s inside. Either way… I doubt there’s anything nice behind that door, Ashok.”

“But it’s a vault, and we have a key. How can you not be tempted?”

“I never said I wasn’t tempted.” Ashok’s curiosity was notorious. He’d fly into an exploding starship if he thought there was interesting tech hidden inside. Callie was more pragmatic… but she was also vulnerable to the allure of the unknown. Her ex-husband used to say Pandora had nothing on her – Callie would have opened that box without hesitation. “But just… imagine you’re an alien, and you land on Earth, and you find a mountain, and there’s a steel door in the mountainside. The door is covered with pretty little symbols, triangles inside circles… all in yellow and black. You might be tempted to look inside, but it would be a bad idea.”

“You think there’s toxic waste behind that door?”

“I think the Axiom fought wars with each other that destroyed star systems. I think they launched long-term projects designed to alter fundamental characteristics of space-time – some of which are still ongoing thousands of years later, as we’ve discovered. I think they plotted to survive the heat death of the universe. I think anything they locked up, with a key like this, in a place like this, could be something we don’t want to fuck with.”

“It could be something amazing.” He gazed up at the door, and then frowned. His mouth was still human enough for that. “Huh. There’s more writing up there, over the door.”

Callie tilted her head back, and saw more of the Axiom script, following the arch above the vault. “Can you read it?”

“Lantern taught me some of the language, and I’ve got a visual dictionary loaded in my external memory. I recognize most of the words… let me see… that’s the imperative case – no, wait, it’s got a warning inflection, hold on. I think it says something like… ‘Open only on the last day of the war.’”

They both stood silently for a moment, looking at the vault.

“Which war?” Callie said.

“How would you know it was the last day?” Ashok said.

Callie shivered. “We can’t. We just… Ashok, we can’t. Whatever’s locked up in here, we should leave it locked up.”

“I get where you’re coming from, but maybe it’s a weapon we could use against the Axiom.”

Callie shook her head. “The last day of the war? If we’re guessing, I’d guess it’s a weapon of last resort. Like, our enemies have taken the capital, the palace is about to fall, let’s blow everything up ourselves so there’s no country left for them to conquer.”

Ashok slumped. “You know how I tweaked my risk-assessment engine to be real comfortable with dangerous activities? Even it’s telling me we shouldn’t open the door. This is officially the worst, though.”

“Make a hole, Ashok.”

He obliged, tearing another rip in the air. They slipped through and sealed the temple up behind them.

“What do we do with the key?” Ashok said.

“Once we get underway, I’ll load the key and the phase-shifter onto a torpedo and launch them both into the nearest star. Your idea was a good one. The phase-shifter will burn up, and the key will be safe there, at least until heat death, and by then everyone will have bigger problems. Maybe the star will become a black hole and the key will be really locked away.”

“Oh captain, my captain,” Ashok said glumly.

The next day, she and Ashok stood in the White Raven’s observation deck and watched the flare of the torpedo’s propellant drive it toward the sun. They stood silently for long moments after the torpedo vanished from sight. A while later, the screen on Ashok’s arm flashed. “Impact,” he said. “The world is a little safer now. A little more boring, but safer.”

“Sometimes that’s best,” she said. “Being thrown into a volcano is probably exciting too. Exciting isn’t always good.” She clapped him on the shoulder. “Next time we find an alien vault, I’ll let you open it, for sure. Okay?”

“Promises, promises,” he muttered.

Back in her quarters, Callie made sure the door was sealed, then opened up the strongbox bolted under her bunk. It wasn’t a four-dimensional vault that could only be opened by a pentachoron key, but it was pretty secure, with a code to enter and biometrics both.

She opened the lid, and gazed at the key inside: crystalline, shifting as her eyes played over it, beautiful and strange and not entirely of this world. Shooting a torpedo into the sun – and talking about their plan to do so on unencrypted comms – had been a necessary deception. Callie had no doubt their mysterious ‘ally’ the Benefactor was still watching them, but she was confident her quarters were secure, at least for the moment.

If the Benefactor had sent them to clear the path in order to take the key, better to make it seem like the key was beyond reach forever. She wasn’t about to get rid of it – not until she had a better idea of what it was for. The answer could be in some Axiom database. In the meantime, she’d keep the key locked away. The universe was full of dangerous things, and Callie liked having them under her control.

Ashok made sure the door to his machine shop was locked, then took the cloth-wrapped bundle containing the phase-shifter from underneath a pile of scrap in one of his work table drawers. Callie had told him to keep the device safe, and to try to figure out how it worked, if he could. They’d discussed destroying it, but what if the Benefactor had a dimensional ripper of his own? They might need to get back to that temple eventually.

Because maybe someday there would be a war. And maybe someday that war would have a last day.

Ashok settled down with his instruments and began to study the device.