Stars, but it felt good to ditch that Force-forsaken suit.

The Emperor would be displeased when he heard of this, no doubt, but Vader wouldn't preoccupy himself with that now. In the streamlined life support module he'd left back on Coruscant, he might've managed it, but Vader was not a small man. The armor on his fortified suit made his shoulders even broader than they already were; waring that, there was no way he'd be able to squeeze into this crawlspace.

He paused halfway through unscrewing the dull grey access panel before him, stuffing the tiny screwdriver he'd been using between his teeth to rake his hair off his face. Those damned med droids had cropped it too close after his last head injury a few months ago, and now it was too short to tie back in a pinch when he needed his vision clear for detail work.

He growled through his teeth and took a few hasty breaths, frustration getting the better of him. A sudden, jarring stutter in his diaphragm reminded him of the inescapable truth that had dominated his life for the last year: going without the suit or the module had consequences.

The inevitable first flash of panic hit him harder than usual, this time, and as Vader spat out the screwdriver he found himself scrambling for the dark side like a lifeline. Liquid courage filled his veins like magma in an instant, and he managed to force his breathing into a slower rhythm with only one more hiccup.

Full, deep breaths, and a steady heartbeat. That was the key.

Retrieving his screwdriver, Vader removed the panel and set it aside. Eight slender data chips gleamed up at him from their ports, but Vader only had eyes for the third one from the left. Sliding the screwdriver between his teeth again, he pulled a code cylinder from his breast pocket and touched it to the chip.

It buzzed after a moment, informing him the data transfer he'd been hoping to make since early this morning was complete. As quickly as he dared with the threat of another flareup looming over him, Vader replaced the panel and began shuffling backwards out of the crawlspace. His borrowed engineer's coveralls had to be hopelessly creased by now, but who would look for the Emperor's second-in-command in the bowels of the least-used comm tower on the entire Death Star?

Vader pulled himself the last of the way out of the crawlspace and dropped to the floor, wincing when his heartbeat lurched. At least this time the flareup passed like a blip on the radar, long before it could really impact Vader's mood. He was left to transfer the information he'd copied to his code cylinder onto his datapad in peace, an eager smirk touching the corners of his mouth.

Summoning the breath for anything more than a low grumble without his oxygen tank and electrical stimulators risked taxing his diaphragm, but he allowed himself the luxury of whispering, "Surely the infiltrator didn't think of this," as if it would somehow make it true.

And it would be, he expected. No slicer worth paying would leave any kind of trail back to their location unless they were in a hurry, with a very reliable escape route only a few steps away. Vader himself had honed his skills until he could slice at phenomenal speeds solely to give himself enough time to cover his tracks. But the exact date and time of the infiltration... those weren't something an average slicer or even a good one typically bothered hiding. And right now, even the smallest, most often disregarded details could tell Vader something about his opponent.

Aboard any Imperial dreadnought, space station, or outpost, a Standard day was split into four six-hour shifts to keep its personnel fresh. Most officers worked two shifts a day, which meant roughly half were on duty at any given time. Slicing security measures as complex as Project Stardust's would require human instinct, not premade computer viruses. Tarkin had made enough pointed remarks about how overworked his crew was already that no one would be able to manage their duties and hack into the system at the same time. Assuming the slicer was one of their officers – which was very likely, loath as he was to admit the possibility of a spy in their midst – Vader could find the infiltrator by process of elimination.

Vader had six transmissions to work with, which had been discovered by chance a week and a half before during the semimonthly purge of recorded outgoing messages from the communications database – all six written in a code they had not thus far been able to hack. Now that the messages had been read by their intended recipients, none of them still had timestamps, only a number to indicate in what order they'd been sent. But Vader had high hopes that this comms tower, which was used to store backups and other logs, still had the answers he was seeking.

The datapad in his hands chimed, and Vader snapped the information from the data chip up into a hologram. With shaking fingers, he typed in the number of the first anomalous transmission into the search function. He snarled in frustration a second later. The screen came up blank, the data chip's storage wiped clean.

Chanting curses under his breath, Vader tossed the datapad aside. This lead had been a long shot, but all his other ideas would take weeks to execute – and the kind of patience he was generally lacking. If he couldn't get ahold of the person responsible for the rogue transmissions and interrogate them about their methods personally, this investigation was going to require a lot more subtlety.

And a lot more slicing.

Vader's diaphragm spasmed. Wincing, he breathed deeply and released his emotions into the Force. It was a Jedi technique, and one he would never admit to Master Tyranus that he still used. But when his life was on the line, it was a lot faster than searching through the chaos in his soul for the eye of the storm.

The door into the room slid open. Not daring to reach into the Force with the light side flowing through him, Vader reached for a lightsaber he hadn't thought to move to the belt of his borrowed coveralls. He forced himself to relax when Kallus strode inside, but not before hissing, "How'd you karking find me?"

Kallus raised a brow. "I know of everything that goes on in this station, Lord Vader. And begging your pardon, but you're not exactly a difficult man to track."

You didn't know there was someone aboard sending unauthorized messages until your ensigns stumbled upon the evidence in the records, Vader thought sourly, but kept it to himself.

"What in the universe are you wearing?" Kallus said, and made a good show of noticing Vader's coveralls for the first time.

Vader drew himself to his feet, tucking the datapad into a pocket and dusting himself off. "Your ability to keep tabs on my movements may be adequate, Agent Kallus," he drawled as loudly as he dared, "but it wasn't to deny myself the pleasure of your company that I was avoiding drawing attention to my whereabouts."

"Forgive me, I didn't catch that. If you could only speak up a touch..." Kallus grinned like a predator that had caught its prey off-guard. Vader tensed, readying himself for battle on reflex. His proclivity for insults was familiar, but the steel behind them was not. This wasn't a side of Kallus he had ever seen before.

"Oh, that's right," Kallus went on. "Your lungs aren't worth much without your fancy life support suits, are they? Your pardon, my Lord, I didn't mean to tax you when you're most vulnerable to the whims of old injuries."

Vader struggled to keep his expression level at a menacing glare. Exactly how much had the Emperor told Kallus about Vader's condition? About his past? Was Kallus deeper in his Master's counsel than Vader had initially suspected? Even more worrying, how much had Kallus found out on his own, the rat?

Vader let the dark side wash over him, lending him its strength and searing away his worry into the familiar burn of anger. Those questions were exactly what Kallus wanted Vader to fixate on, keeping him off-balance, blinding him. He couldn't let his guard slip; that would only give Kallus the chance to launch another attack from a different direction.

Kallus glanced with distaste around the cramped room Vader had been operating out of for most of the day. "So this is where you slithered off to."

Vader managed to stop from rolling his eyes as he reached Kallus' side, but only just. In the past few weeks he'd grown to rely on the impassive front his helmet afforded him, but he didn't have the luxury of making faces at people any longer. "My congratulations, Kallus. You've found the serpent's den." Grinning wickedly, he added, "Pray he does not decide to strike you. Nothing puts a born killer in a worse mood than infringing on his territory."

Kallus hid his fear well. "But could your heart handle the strain, my Lord?"

"You've been a thorn in my side for the past year," Vader growled. "Could yours, if I decided it was time to return the favor?"

This time, Kallus balked. Good. Vader had no patience for his sniping today.

"So, what's your excuse for disturbing my work this time, Kallus? This tower is about as far from the overbridge as you can get." This time, Vader didn't bother concealing the eye roll. "Couldn't resist sticking your fingers into my investigation?"

" 'Your' investigation? Emperor Serenno was clear that this was to be a joint effort, and yet you've spurned my help at every turn. I could've told you this tower would be a dead end. Our best people have triple-checked it."

Vader opened his mouth to retort that he was better than Kallus' best, anger sparking higher in his chest, but Kallus beat him to it. "If threats are the only language you speak, Lord Vader, then threaten away – I can match you well enough. But don't insult me with by implying I need excuses to inspect my own station. Tarkin may be in charge on flimsi, but Stardust falls under my jurisdiction as head of the ISB. He reports directly to me."

For once, Kallus was only a shred below making himself painfully clear. Vader had long suspected he couldn't say anything without varnishing the true meaning of his words with at least one coat of deception and misleading diction. Still, it was a refreshing change from the usual half-dozen. But there was that steel in Kallus' gaze again, transforming him from an unassuming sycophant into a deadly predator. Something about it was chillingly familiar, making instincts deeper than the Force come alert in Vader, telling him to shy away.

Vader looked Kallus over, and perhaps for the first time, he really looked at him. Kallus was two or three years Vader's elder, and he moved with an aristocrat's grace where Vader had the easy stalk of a trained killer. With his brown eyes, golden tan, and hair a shade or two darker than his skin, he could've blended in with the populations from half a dozen worlds. His squarish face might've been considered attractive by some, if not for his massive sideburns.

Whatever it was Vader was missing about Kallus, he couldn't see it with his eyes alone – and thanks to the Emperor's tutelage, Kallus' shields were thick enough that rifling around in his head wouldn't be worth the effort. Vader drew himself back to the situation at hand, and considered what Kallus had told him.

Vader was at a disadvantage here. He could always threaten demotions or promise promotions in exchange for intel because he had the Emperor's ear, but Kallus had the same privilege – and Kallus was at the top of the station's command structure. Kallus didn't have to fight for scraps at this particular table. He had the pick of the choicest morsels of every dish. Vader would be foolish not to capitalize on that, the same as what he'd done with Rehin and Lady Noronessa.

Plus, the Emperor expected him to tolerate Kallus long enough to get to the bottom of these rogue transmissions. Skilled as he was, slicing wasn't getting him anywhere; his opponent's defenses were too solid to probe without better leads. If playing nice for the time being gained Vader information he could use, well, knowing he'd bled Kallus dry would only make sliding a poisoned needle through his ribs that much more satisfying later.

"Walk with me, Agent Kallus."

Kallus' response was to plant his feet firmly on the deck plate, his arms crossed and expression sour. "I have no intention of spending long it takes you to reach the next computer console running at your heels trying to plead my case, Lord Vader. If you don't wish to collaborate, fine. But when the Emperor asks why we've made no progress in our next report, I certainly won't take the fall for it."

Vader pinched the bridge of his nose. "I asked you to walk with me, not to follow me, you karking fool," he gritted out, loud enough in his irritation to make his diaphragm jump once before stilling. "Aren't you supposed to be good at reading word choice?"

Kallus still looked mistrustful, but frankly, Vader didn't really care. All he needed from Kallus until he outlived his usefulness was his cooperation – and, when Kallus fell into step beside him, Vader had a feeling Kallus intended to give it.

"Tell me something, my Lord. Why are you so convinced the Rebellion has infiltrated the station? Have you sensed something in the Force?"

"Not I. But the Emperor himself decided your and Director Tarkin's reports of unexplained transmissions were worth looking into. Even if he's being overcautious, I trust his judgment. Project Stardust is vital to the future stability of the Empire. As for the Rebellion," Vader said, working his hands in and out of fists, "only fragments of those original outgoing messages remain that weren't scrubbed from the system, but they're written in code – and not one of ours. That suggests a Rebel presence, or at least that of a third party interested in getting their hands on this technology."

"Until the station is fully operational, no one but the command staff has the clearance to send messages without approval. Even the division leaders have to pass through Director Tarkin to confirm shipments of parts and construction materials."

"A skilled slicer can find ways around even the tightest of restrictions."

Kallus nodded thoughtfully. "And whoever this hypothetical infiltrator is, if they're a part of the Rebellion, they were certainly clever enough not to transmit on EF-4. Even if it loses them the security of knowing we can't listen in, it would be a simple matter to conduct searches for Republic tech."

Vader had to force himself to breathe evenly. "A simple matter? The Death Star's surface area is expected to surpass eighty thousand kilometers squared! I can't fathom the amount of possible hiding places that leaves, even with the station still unfinished. Why do you think my first instinct was to search the comms systems for evidence of tampering and follow the trail from there?"

"You made your point very clearly that the vast majority of Project Stardust will be for show when you first arrived," Kallus said with a hint of disdain. "But at present, to minimize security risks, we only have a skeleton crew aboard. It's more sensible to depressurize the station's unoccupied regions and forgo life support. Most of the construction on the outer hull is being done by droids, and access to vac suits is strictly limited."

"So the infiltrator must be an Imperial officer, then."

Kallus nodded hesitantly, conceding the point. "It... would seem that way."

"Then we must proceed as though that were a given fact."

They were approaching the more populated areas of the station, and Vader's rumpled coveralls, single gloved hand, messy hair, and yellow-red eyes with circles he could never get rid of no matter how much he slept were drawing curious looks. His nerves ticked up a notch, and he clasped his hands behind his back to keep from fidgeting. At least now Kallus, too, had to speak quietly to avoid being overheard, forestalling the next taunt about Vader's shortcomings he was had a feeling Kallus was still looking to land. It was a small victory, but it was better than nothing.

The Force thrummed in warning, and Vader snapped his senses outward in razor-sharp probes, searching for its source. He relaxed some when he sensed only the presence of Galen Erso, head of the senior staff – the group ranking just below the commanding officers like Tarkin – approaching, seeking to speak with Kallus. But he tensed again when he realized what that meant.

The odds were slim Erso had ever seen Anakin Skywalker before, but there were many other formerly Republic scientists and officers on the Death Star. Several of them, Tarkin included, had known Skywalker personally. Vader had made a point of going everywhere with a heavy cloak and the respirator of his life support suit to obscure his face. Now he had neither. If Erso connected a strange-looking engineer to the legendary Darth Vader, there was a chance he'd mention the glimpse he'd caught of what lurked beneath the armor to someone who could connect the dots.

Vader was shocked by how much that terrified him. But there wasn't time to delve for the source of his terror now; he had to get out of here while there was still time. "Galen Erso is around the corner. I sense he wishes to speak with you," Vader said in a low rasp, pulling to a stop. "I'll take my leave."

"What? How did you–?" Kallus laughed lightly. "Of course. The power you share with the Emperor is quite beyond me at times, but I appreciate the advance warning. I was expecting him to seek me out, and speaking with him should only take a moment. If you'll forgive a short wait, my Lord, I can join you on your next–"

"Your presence will not be necessary, nor would it be welcome," Vader broke in bluntly – too bluntly, he realized, if he still wanted to soften Kallus up. Thinking quickly, he added, "I intend to meditate on the infiltrator's identity and goal aboard the Death Star."

"Ah. In that case, I see," Kallus said, a customary jibe suspiciously lacking. "Good day, Lord Vader."

Kallus turned on his heel and continued on down the hallway. Vader made to do the same in the opposite direction when he felt a sudden, dark flicker of emotion from Kallus through the man's usually impenetrable shields.

Intrigued, Vader darted into a nearby alcove occupied by two turbolifts, hunching over and tapping his foot to give the impression of waiting for the doors to open. On a whim, he grabbed the datapad out of his pocket and turned it on. It would give him an excuse to avert his gaze and conceal his gloved prosthetic hand from prying stares behind the device's screen.

The Death Star's halls were dim, the floors and ceilings nearest to the walls inlaid with cool green lights. It was an aesthetic rendition of a Confederate-era tactic to save power aboard dreadnoughts crewed by droids, whose photoreceptors saw far better in the dark than most humanoids. Even with his enhanced senses, Vader nearly missed it when Kallus turned, his gaze slicing down the hallway behind him.

That same harrowing, predatory look lit Kallus' eyes with a cold fire, chilling Vader more than he cared to admit. Then, at last, he recognized it: vengeance. Kallus craved revenge with a thirst so deep it could make a dust ball out of a lush ocean world. Vader himself had only ever felt its like disguised by good intentions or clouded by the weak excuse of justice.

Around Kallus, the Force darkened into a maelstrom of anger and jealousy so rich Vader half-expected to see his eyes flash yellow. And at its frigid center, a crudely rendered effigy of Vader was burning.

Then Galen Erso scurried up, and just like that, it was gone.

"Erso, I told you I'd meet you at the commissary."

"I'm sorry, sir. I, ah... I was nervous."

"There are too many prying ears here," Kallus snarled. He dragged Erso out of sight, and Vader heard two sets of bootsteps move away, one stumbling, one at a hurried prowl. "Come on, quickly. I don't have all day to hear your report."

Vader stilled, hardly daring to breathe – and not because of the spiderweb of electrical burns lacing his chest and the flesh beneath. He was torn between caution and elation, simultaneously certain this couldn't be so simple and darkly overjoyed he'd cornered Kallus at last. He'd initially suspected Tarkin might be in league with the Empire's enemies, but now, after a year of weaving in and out of Kallus' deeply infuriating acquaintance, the man was finally starting to show some complexity.

And what of Galen Erso? He was a nervous man, and a mediocre liar at best. He couldn't hide from Vader's scrutiny, but his role in furthering Project Stardust was vital; if he was keeping secrets, that had the potential to be very problematic.

One of these days, Vader would catch them unawares and pick their minds apart to discover what they were hiding. But not now. Though he was itching to follow them, the station's hallways were uniform in construction – and, to meet Tarkin's high standards for station-board operations, utterly lacking in crates and spare tech he could use as cover. Vader couldn't tail them without being spotted.

Let them scheme if they wish to, Vader told himself, and finally reached for the button to summon the nearest turbolift. I can be patient. When they slip up again, reveal more than they meant, I'll be waiting. Right now, I'm going to meditate. Perhaps this time I'll finally learn something more about Onderon's elusive mystery Jedi.

Vader has been stuck chasing ghosts for nearly a month – first around the auction house on Onderon, and now on the Death Star – and he is not a man accustomed to failure. Nor, for all his fabled patience, is the Emperor. Is Vader truly as indispensable to his Master as he seems to think? With few avenues open to him but collaborating with a suspect rival, will he manage to get to the bottom of this puzzle? Exactly how much of what's happening on Onderon is he aware of through his two operatives now that he's away from the action? Only time will tell...

Hello friends, I just finished binging Leigh Bardugo's Rule of Wolves and I am D E A D. This is one of those times when I'm really glad for ready-made SOTE chapters and quasi-ready-made author's notes, because wow, I can barely summon coherent thought right now. But before the binge began, I was VERY productive (I wrote something crazy like 10K words for SOTE in one week, which is the better part of three chapters) so good things all around!

By this point, you guys have probably noticed that Kallus is a bit different in this universe than he is in canon. I can't say much about it right now, but this Kallus is very much a political creature hardened by diplomatic incidents instead of skirmishes on the frontline. Plus, in exchange for all the power he's been given, he has the Emperor's scrutiny to contend with, which obviously makes for a wild push and pull of character as he balances obedience with whatever gains he can get away with. The best comparison I can come up with is that SOTE Kallus is like a Star Trek Mirror Universe version of who he is in canon, which makes him into a very interesting foil to Vader.

I know, I know, bringing Star Trek up in a discussion about Star Wars is sacrilegious and you can all burn me at the stake for heresy now. But hey, it is what it is.

I'd also like to explain Vader's condition in a little more depth here. In this fanfic, Vader has neuropathological problems – damaged nerves in his heart and lungs, specifically – and he has to wear a life support module or suit that supplies him with purer air using an oxygen concentrator and stimulates his partially paralyzed diaphragm so he can breathe it. I'm no doctor, and I've never been electrocuted, but I went down a real rabbit hole researching potential damage from the massive electrical shock Vader took to the chest during the Battle of Felucia, and I've been trying to handle the topic with as much respect and portray it as accurately as I can. He was trying to lay low in this chapter, which meant it was a great opportunity to highlights the quality of life he has without medical help now. That's something that will be relevant as his character arc progresses.

Next chapter, we'll touch base with the Rebellion and get a sense of how Lux is coping with his father's mandate to marry. I'm going with the same updating-every-Wednesday schedule I had before my hiatus for now, so I'll talk to you all then!