That season three promo though…#missileblocked.

This update is for ScorplinginTraining, who demanded it on threat of shirtnapping. I have to admit that I debated over the reveal in this chapter for a while…but I think Collins (or my version of him, at least) is just maniacal enough to do it. At any rate, it was a very difficult chapter to write, so if you're enjoying the story, don't ignore that little box at the end! Fill it with words, emojis, candy…whatever floats your boat.

"You're bluffing. I don't forget anything."

Walter dug his nails into his wrist. He was going to have to sound a hell of a lot more convincing than that. What was it about his former partner that made him doubt himself, fear himself, hate himself? No one else had that power over him; at least, not anyone who would wield it the way Collins did.

Logically, though, Walter knew exactly why he was so hesitant. He sunk painfully, unforgivably low with Mark. He became a person he never expected or wanted to be. He turned on everyone that cared about him and put all of his faith and trust in Collins. And then he betrayed him too.

Walter hated the twisted genius. But not as much as he despised himself for letting Mark win over and over again.

"Technically accurate." Collins smirked and leaned back into the chair, mercifully vacating Walter's personal space. He pointed his finger in the genius's direction before clasping his hands in his lap. "When you're lucid. Tell me, when was the last time you…lost awareness?"

Even you don't know everything.

Or maybe you do know, and you just don't want to remember.

A fresh wave of dread pooled in Walter's chest. He couldn't even count the number of times he'd gone down the rabbit hole with Collins, although he was sure Sylvester had the precise figure stored somewhere. Walter could easily lose hours, days, weeks lost in a vacuum of his own thoughts, with limited to nonexistent perception of the outside world. Happy wasn't exaggerating about bringing him back from the brink of starvation after one particularly intense journey.

The only thing he knew for sure was that Collins was present for every second. If there was a secret that even Walter couldn't readily access, it was hidden there. Jumbled in with flashes of memory and darkness that he'd tried his best to forget.

"Not since you left. Funny how that worked out."

"Hilarious," Collins said flatly, crossing his arms over his chest. "No wonder you haven't made any noteworthy breakthroughs in four years. A few days down there and you might have actually found a cure for Megan's MS."

Walter's breath hitched at the mention of her name, and Mark knew he'd hit a pain point. The genius could hide his emotions from everyone on earth except the man sitting across from him. The most dangerous man he had ever met.

"But that would have been a sacrifice, wouldn't it?" An almost delighted smile passed over Mark's face and he spoke with more confidence, like a cold reader getting closer to his mark. "One that you couldn't afford. After all, Happy had threatened to leave if you went down again. Toby and Sylvester would follow her. Cabe wouldn't understand. And Paige…oh, Paige." He shook his head slowly, his grin widening. "She's never seen that side of you. Far too unstable. Say bye-bye to the liaison and her son."

Walter put all of that behind him years ago. He'd never really considered Paige's reaction because he was resolved never to go there again. The temporary boost in his mental capacity wasn't worth his team or his life.

"I've seen you make incredible strides when you were down. You had ideas that could have changed the world. But apparently your sister wasn't quite worth that risk, was she?"

Collins looked supremely satisfied with himself. He was baiting Walter. Silence was the best defense, but damn, did he make it difficult.

What was there to say, anyway? That Megan was his world? That he would have done anything and everything to save her? That even now, he would willingly give up his life in exchange for hers? That she was special and merited much more time than she was allowed? Those things were all true, but Collins didn't deserve to hear them, so Walter pressed his lips together and swallowed the words.

When he didn't respond, Collins nodded at Walter with what could have been mistaken as respect by someone who didn't know better. But he did. Mark was stalling. They were wasting time and he wasn't sure why.

After a long pause, Collins furrowed his eyebrows and sighed theatrically. "That's not what I came here to talk about anyway. I suppose you already guessed that?"

Walter huffed out a breath of his own, his frustration steadily growing at the other man's relentless misdirection. "Well why don't you just get to the point and tell me—."

"The man in the red shirt," Mark interrupted, studying Walter carefully for any hint of recognition. "Dark hair…brown eyes…six foot one. Keys on his belt loop that made noise when he walked. Obnoxious prick. Do you remember?"

Walter recognized the description immediately, but what Collins was telling him was impossible. He'd only seen that man once, in a nightmare he had five years earlier. Typically, he had control over his dreams—at least enough to play them back later in detail—but he admitted that this was different. It was fragmented, like a movie with scenes missing. And what Walter could remember, he was loathe to revisit. He hadn't told anyone about it. Unless it helped to solve a problem, Walter mostly disregarded his subconscious thoughts.

Collins could almost pinpoint the exact moment he realized the truth.

"No. No," Walter spat back, struggling to draw a breath like the air was being manually sucked out of his lungs. "I told you. I don't know why but I…I must have…"

"You didn't have to tell me, Walter. I was there." Mark reached over and took one of Walter's hands between his own, although the genius's head was spinning too much to register the contact or react. "Deep in the recesses of that brilliant mind, you know it wasn't a dream. You see it, don't you? What you did? Let it come back to you."

"I don't—I don't want to," Walter said weakly, his vision blurring slightly as he met Mark's expectant gaze. "You're manipulating me. It never happened."

"Stop hiding from it," Collins demanded, releasing his grip and placing his hands on Walter's shoulders, anticipating the genius's sudden urge to bolt. "Stop fighting it, Walter. This is what binds us together. You can never accept who you really are until you let yourself remember."

It couldn't be real. Rabbit hole or not, Walter would never…but everywhere he looked, the evidence was there. The blood. The tools. The chemicals. This wasn't the first time he'd seen those things, but he had always dismissed them as hallucinations from his overworked, sleep-deprived brain.

It couldn't be real.

But Collins had proven he wasn't above murder.

Walter dropped his head into his outstretched palms, the pounding of his heart echoing through every part of his body. Was Mark gaslighting him? He had to assume this was a trick until he saw evidence. But he didn't want proof. He didn't want it to be true. "You killed him."

"Yes," Collins said evenly, no trace of concern or remorse in his voice. "The rest, Walter. We've buried it long enough. It's time to remember."

The genius clenched his hands into fists until they ached, as if he was searching for the right trigger to escape from this nightmare. But the images in his head were too clear now to ignore. Too real to forget. "And I helped you."

Sylvester shoved himself away from the desk and stood up abruptly, tugging a section of his hair anxiously with his fingers. "This is pointless. Walter's a better hacker than all of us combined. There's no way we'll figure out his lockdown code in time."

Cabe set down the file he was reading and crossed over to the mathematician, putting a comforting hand on his shoulder. "It's alright, kid. Just take a break and keep trying."

"No, you don't understand." Sylvester glanced over to Toby and Happy, who heard the commotion and joined them, and shook his head fervently. "I can't even get fifty lines into it before the code starts to change. Walter designed this to be unhackable. It'll protect itself against any virus we introduce. He's the only person who would even have the first idea how to attack it."

"Well, we can't just leave him to fend for himself in there," the agent grumbled. "Even if he can take on Collins, we have to assume there are other factors that we don't know about yet. Mark always has a backup plan. Are you sure there's no one else who can get control of the lockdown?"

Toby cleared his throat, earning the attention of the group, who turned toward him in unison. "There might be. But it's risky."

"Ralph," the mechanic sighed, dragging her hand over her mouth. "He's smarter than Walter and knows how he thinks. If anyone can get inside Walt's head and figure out how this code was designed, it'll be him."

The psychologist dropped his head. He couldn't believe what he was suggesting. Walter would kill him for even bringing it up. "But we'd almost certainly be putting them in danger. Hacking into the garage's computers is a surefire way to get attention from Collins. We can help cover up the source, but if Mark finds them, they're screwed."

Happy tipped her chin toward Sylvester. "What are the odds?"

"Assuming that Collins is anticipating a hack…" He hesitated, shifting his weight between his feet. "Seventy-three percent."

Silence fell over the team. Everyone knew it was their best option, but no one wanted to be the first to push for it. They'd made a promise to protect the liaison and her son, and if Walter was there, he would tell them to leave Paige and Ralph in peace no matter the consequences.

But Walter wasn't there, and if they didn't do something, that was going to be their new normal.

Cabe nodded affirmatively to Happy, who pulled the encrypted phone out of her pocket and handed it to him. He inhaled deeply before pressing the liaison's number. "It should be Paige's decision. Whatever she says, we do."

No, no, no. This couldn't be happening. Walter thought he was ready this time…ready to fight, to win, to reclaim his life and start a new chapter without Mark's poisonous influence. But Collins had one more ace up his sleeve. He always did.

Walter's only logical option was to dismiss the allegations and cling to the steadfast belief that his former partner was torturing him with an illusion. But this…this wasn't like the other times Collins had tried to plant doubt in his head. The other man typically started off with generally insulting statements, zeroing in as he detected a negative response, pressing in tighter and tighter until Walter was insecure enough to play into his hands. He was being far too specific now, far too confident. If it was true, if there was even a chance…the genius couldn't let it go. He needed to know for sure. "W-Who was he?"

"Randall Horton. An astronomy professor at UCLA." The disaffection in Mark's voice was too much. Walter wanted to shake him, hit him, make him feel…pain? Anger? Did he feel anything anymore? "I suppose you're wondering why. It doesn't really matter, but you have gotten oddly…moral as of late."

Walter dropped his hands from his face and glared at Collins. "It matters to me," he said bitingly.

"If it will make you feel better," Mark shrugged. "Well, it won't. But it's a simple enough story. Horton and I worked together on several projects regarding dark matter. He wasn't a genius, but not so insufferable as the other stuffed shirts in his department…until he stole my research. We had a disagreement. I won."

Collins was right. That didn't make him feel better. Walter ran one hand through his hair, twisting it between his fingers as pain tinged his scalp. A small part of him—a rapidly diminishing part—still hoped this was a dream, and he'd wake up in seconds, asleep at his desk with a bowl of soggy granola awaiting him.

No such luck.

So he pressed on. "Why did you ask me to help you?"

"Oh, I didn't have to ask," Collins responded quickly, the corner of his mouth lifting. "You'd been down the rabbit hole for sixty-four hours already. You barely knew who I was. Heck, you barely knew who you were."

For a brief second, Walter was transported there again. Not the deepest he'd ever been; he didn't remember those times. He could still recall the levels closer to the surface, though, the beginning stages. The genius shut his eyes, allowing the vision to wash over him, hoping for some kind of clarity. But everything was pitch black around him, and he felt lonely and cold and…

Walter jumped up from his chair, nearly knocking it over. He suppressed the overwhelming urge to vomit and placed a hand on his desk to steady himself. There was a time when he'd appreciated that place…thought of it as an asset in his work. After four years away, though, even the memory of it scared the hell out of him.

"I knew you wouldn't be able to handle it anymore," Collins remarked simply, looking up at him. "You're too weak. You don't deserve that kind of power."

The genius steadied his breathing again, gradually lowering himself back into his chair. "Keep it," he mumbled as he trained his focus on the floor. "It sucks."

Mark chuckled lightly. "I suppose you could say it worked out better for me than for you. Are you ready to hear the rest of the story?"

Not really. But Walter was too deep in to stop now. He nodded.

"I invited Randall to the garage to talk. We never got past the parking lot. I dragged him in here," Collins gestured broadly to the main office space, "and made a list of the ingredients we'd need. You took care of everything. All I had to do was dump him in and erase the camera footage."

"Dump him in? What does that…" Walter regretted asking immediately. Mark's expression confirmed his awful realization, and it wasn't long before the genius was grabbing for the trash can under his workstation and emptying the meager contents of his stomach. "Oh God. Why did—why would—."

Collins seemed unfazed by Walter's obvious distress. "It was efficient. No body, no crime."

Walter threw up once more for good measure and then shoved the can back onto the floor, the smell assaulting his senses. How? How could he have ever agreed to this? Mistreating his family and friends when he was down the rabbit hole was one thing. Forgetting to eat and sleep…but getting rid of a body? He could see the chemicals Collins was describing as they were lined up on a table, saw himself measuring them out into the large, oval-shaped metal container that they used for experiments, but the body was missing. Walter supposed he should be grateful that part was blocked out, at least.

"I always thought…" Walter swallowed, his throat burning. "I always thought there was still an ounce of humanity left in you, but I was wrong. You used me. You used me to kill someone. Do you understand how insane you are?"

Collins held up both hands in mock surrender. "I can see how you'd feel that way. Although I would argue that he was already dead before you got involved, so to say that I used you to murder him is a tad dramatic…"

"Damnit, Mark!" No longer concerned with the consequences, Walter lunged forward and grabbed Collins by his shirt collar, clutching it tightly enough to restrict the other genius's airflow. "This is all a big joke to you, isn't it?" he snarled. "You've been ruining my life as long as I can remember. If I was lucky, Horton would have killed you that night instead. It would have been a service to humanity."

The man looked vaguely surprised at Walter's outburst, but made no move to get out of his grasp. He merely blinked a few times and then smirked. "It's easy to blame everything on me, isn't it? I'm your Boogeyman. Your scapegoat for every bad decision you've ever made. Pretending that I'm some sort of monster makes it easier to avoid taking responsibility. You were there too, Walter. I didn't force you."

Walter released his grip on Collins almost violently, throwing him against the back of his seat, and rose again, pacing in a line along his desk. "What would you call it?" he barked, linking his fingers behind his neck before dragging them back around to his face. "I was down the rabbit hole. You knew I was in no condition to make decisions; I was barely functioning…"

"And whose fault was that?"

Mark's question stopped him dead in his tracks, and he spun around, surprising himself with the venom in his tone. "What?"

"I said, whose fault was that?" Collins enunciated, standing to match the genius's height. "I've done a lot of things to manipulate you, Walter, but I never pushed you down there. I never had to. You craved it. You wanted the freedom and the opportunities it gave you. So stop painting yourself as a victim." He took another step toward Walter, his eyes growing fiercer. "Would you say that an addict isn't responsible for what he does when he's in oblivion? It was his choice. He decided to lose control. You knew exactly what sent you to that place, and you went willingly. You gave up control for something better. And just because you're regretting that now doesn't mean you don't have to live with it."

Walter stared at his former partner. Was he guilty? He couldn't even begin to address that question right now. He was still reeling from the knowledge of what he'd done. Everything felt so wrong. "Why can't you just let me live?" he breathed, the anger draining from every cell in his body, replaced with a crushing weight that made it difficult to even stand. "Let the past go. Leave and start over somewhere else. Anywhere but here."

Collins shook his head. "You can fool them, but not me. The only thing that separates us is that you're still clinging to this…this lie about who you really are. And I'm not leaving until you accept that you are meant for so much more than this. A life far beyond the confines of this garage and the people in it." He closed the distance between them, and for the first time in years, the genius saw them as they really were. Equals. The thought chilled him to his core. "Trust me, Walter. When this is all over, you'll thank me."