A/N: This turned into the longest interlude yet. More than twice the word count it was supposed to be and I had to force myself to end it. That's how much I enjoy writing these two.

For days after his odd dream, Ford Pines buries himself into research.

Well. To be entirely honest, he's always buried in research: it's what he does best, and what he loves most. What changes now is the subject of his research - one that pops out simply everywhere he looked, now that he knows what to look for.

"Even in my wallet," Ford mutters, resting his elbows on what little free surface the table had that was not covered with books, scrolls and notes. He presses the heels of his hands against his eyes, which are reddened and feel scratchy from the lack of sleep.

The Eye of Providence, references to a being with answers, to binding contracts and amazing events and feats whenever those were involved. How could he not notice before? How could anyone not notice?

"They didn't know where to look."

Bill's voice comes suddenly from right behind him, causing him to wince and turn around. There he is, hovering in mid-air, eye on the clutter on the table. He gives a low whistle. "Wow. You really get serious about research, don't ya?"

"I thought you couldn't come into the physical world."

"I can't. You fell asleep, smart guy. With your glasses on. That's gonna leave a mark," he says, and comes to sit on Ford's shoulder. He does feel solid, and it's hard to remember that, at the moment, they are both just astral manifestations of themselves. "So, what did you find out?" he prods, an elbow resting over Ford's ear.

The smugness in his voice is such that Ford can't hold back a laugh. "It's how you said. You're all over history."

"See? Shoulda taken my word for it instead of staying up researching for, what, forty-nine hours?"

What, was it that long? Ford glances at the far wall, where the clock is, but he can't read the time: there is a smiley face where the numbers and arms should be. Bill shrugs.

"Don't bother with time. You're dreaming, so it doesn't count. Just- whoa. You've got some fluffy hair right here, Fordsy."

Ford blinks. "Er… thanks?" is all he can say while Bill stands up on his shoulder to ruffle his hair with both hands.

"And look at that, no lice! You humans sure have come a long way from where you started," he says, and Ford feels his - scarce - weight being lifted from his shoulder and then dropping on his head a moment later. "Comfy!"

"... Are you making angels in my hair?"

"Let a muse have some fun," Bill retorts, but he does lean over so that he's looking into Ford's eyes, just upside down. Even so, the hat perched on his hea- upper angle doesn't fall. "I mean, there's a lot of work ahead of us. May as well get started with the right spirit, partner."

Partner.

It's been a long time since last time anyone has called him that: the last one to do so was Stan, and afterwards… well. He hasn't truly spoken much with anyone there in Gravity Falls, but college wasn't that bad. He had actually made a friend for himself for the first time - but with Fiddleford it was always 'buddy', never partner.

He has missed that.

"Your turn to roll the dice!"

"... I thought we were supposed to do science here."

"There is science behind all of this!"

"Is there?"

"Roll the dice to see how you fare against the illusions of Probabilitor the Annoying! Yes, that's the way to... Yes! Look at all that damage! It's over 9,000!"

"Huh. Great. Can we get back to-"

"With pen and paper, shield and sword, our quest shall be our sweet reward!"

Okay. Okay. You can do this, Cipher. You need this guy. You can do this. It won't be long.

Bill Cipher cannot recall a moment in his existence - over a trillion years now - when he's been speechless.

Apparently, there really is a first time for absolutely everything.

"What do you think? I did some redecorating!"

"Huh…" Bill says, eye shifting from the tapestries bearing his image to the pyramidal crystals, to his image on the carpet and then to the golden, amazingly tacky statue of himself on top of what's nothing short of a shrine. "... Where did you even find that?"

"I dug it up!" Ford exclaims, sounding incredibly proud of himself. "Must be something the ancient natives left behind! It must be over 2,000 years old - amazing craftsmanship for the time! I figured it would be nice to give it the place of honor. Do you like it?"

There are very few things Bill enjoys more than flattery, and even fewer things he likes looking at than his own image: his palace in the Nightmare Realm is full of portraits, and statues of him are pretty much everywhere across the dimension. Sense of measure is not precisely something he has in spades. And yet…

You're creeping me out, Sixer. Congrats. Takes a whole lot to creep me out. Maybe we should take a break or something? See other people?

But of course that's not an option: the portal must be done, and Stanford Pines is the guy for the job. At least this is a good sign - it means he trusts him… right?

"... Love it, Sixer," Bill finally says. "Did a pretty great job with the place. Oh, hey, I think someone's calling from hyperspace. Be right back!" he says quickly, and disappears from Stanford's mindspace before he can say anything more.

"You know, you're welcome to stop laughing any time this millennium."

"Hahahahahaha! Oh gosh- hahahha! I'm sorry, but this is just too cute! You went to get a tool and got a fanboy! Did he - heeehe! - did he already ask to keep your bowtie so he can sniff it at night?"

Bill rolls his eye and finishes his glass in one go. "No. Coulda lived without that mental image, Ronnie. Thanks."

"Anytime!" Pyronica grins at him, then pokes his side. "Look on the bright side, boss - you sure got him good. Getting him to open up the passage will be a child's play!"

"True," Bill concedes. He has to admit that, when he's not creeping him out or trapping him into never-ending, amazingly boring board games, Stanford Pines is, by far, the single best pawn he's ever had.

Like many before him, he loves to have his ego stroked. He relishes in flattery, and that makes him gullible. His issues help, too, issues so obvious Bill hardly needs access to the depths of his mind - a clever mind, he has to admit, one he'd like to know more about - to see them.

A birth defect, never feeling like he belongs, the connection to anything unusual, the need to prove himself by going beyond anything achieved before - it all adds up to a chronically insecure human who sees in his own intellect his only true strength, perpetually searching for a big break, knowledge and validation.

In short, the very best puppet material.

"Hey, maybe he'll even join the party when we can get it started! It's been forever since we got someone new in the gang!"

Bill can't say the thought hasn't crossed his mind - because a freak would fit right in with freaks, wouldn't it? - but it's much too early to call it. He can't take risks by letting him on what's really in the works until the deed is done. Then he'll make his offer, and see if Stanford Pines is really as smart as he thinks he is.

"... And so the moon landing was faked? Are you positive?"

"Absolutely. The moon doesn't even exist - the thing you see up there is a disk hiding alien space surveillance."

"Ha-ah! I knew that landing couldn't possibly be real! There are too many things that don't add up, like-"

Stanford prattles on for a while, and Bill lets him. It's not very difficult to guess it isn't often he gets to ramble with anyone about his discoveries and theories; it's not very often he speak with anyone at all, really. By now he knows his habits - that he has just about everything delivered to his home, and has hardly met any of the townfolk a few times, exchanging even fewer words. Works for Bill: the fewer people approach them now, the easier this will be.

Now that Stanford thinks he has found a kindred spirit, it seems that the floodgates have opened. He talks and talks, asks questions, talks again - and he's eager to see him, to the point he has started taking mild sedatives to sleep more before Bill shows him how to enter the mindscape through meditation.

Of course, there is a catch to be able to do it. Well, not really - but Bill lies, he always does, and Stanford Pines falls for it hook, line and sinker. To no one's surprise.

"I've got to have free access to your mind, Sixer. Will make it a lot easier for you to get in touch whenever you want - just think you wanna talk to me, and I'll come over. I'd also be able to borrow your body. Kind of a big thing, really, so if you wanna think it over-"

"No need," Ford cuts him off. "I have already made up my mind. You're free to come in and out of my mind any time you wish. There is so much we can accomplish as a team, and I couldn't possibly trust you more!"

That seems just so easy that Bill, as much as he loves it when things are easy, pauses and blinks. "... Are you being sarcastic?"

Stanford seems taken aback. "What? No. Why would I?"

So, he's really that dumb. Oh well. Works for him, Bill thinks, and shrugs. "Just checkin'," he says, and holds out his hand. "So, deal?"

"It's a deal - from now until the end of time!"

"Just let me into your mind, Stanford!"

"Please, call me… a friend."

A friend. This puny meatsack thinks himself his friend.

Bill laughs and laughs and laughs - but only after he's shaken his hand, and the deal is done.

"Your hair is really fluffy!"

"Bill. You're pulling it out."

"Hey! What was that?"

"What was what?"

"Some kinda tingly thing in your head. When I pull like this, see?"

"I'm guessing it was pain. You really shouldn't be doing tha- watch out for the stool!"

"Whoa!"

Crash.

Ford winces and covers his eyes with non-corporeal hands. "Bill?" he calls out, not daring to look.

"Hahahahah! This is amazing!" Bill's laugh reaches him, and he dares to peer down at… well, his own body, doing angels among scattered papers and books that were on the table Bill collapsed onto only moments ago. The grin on his face is impossibly wide, and two yellowish eyes with slit pupils turn up to him. "I had forgotten pain was a thing! And hey, hey, check this out!" he adds, closing an eye, then the other, then the other one again, a finger pointed up at him. "Now you're here… now there! Now here! Now there again!"

Ford finds himself chuckling. For an all-seeing and all-knowing being, he's surprised by the most ordinary things. But then again, why would an immortal being older than their galaxy - older than time itself, Bill had boasted once - care to know what life as a mere human would be like? "It's a matter of perspective. It happens when you have more than one eye, and they're not in the same exact position."

"Oh! And this!" he adds, and sticks a finger in Ford's mouth, biting down on it. "Can keep my eyes open while chewing!" he announces around his finger.

"... I might be best not to bite on that," Ford says, more than slightly worried he might bite it clean off. Bill laughs again.

"So? You've got extras anyway," he says, but does pull the finger out of the mouth and grins up at him, elated. "Wow. I mean, wow - everything hurts everywhere!"

That's not precisely something Ford has ever heard said with such cheerfulness before. It's kind of worrying, really. "... Nothing's broken, is it?"

"Naaaah," Bill drawls, and rolls over his - Ford's - stomach. "Okay, okay, gotta get up. I've got this. Just... how do you balance this thing?"

"Through the vestibular system. In the inner ear, there are three semicircular canals that-"

"Hey, hey. Gimme some credit, I know the technical part. Just gotta figure out how- I've got it! I've got it!"

Bill sways a lot one way and then the other and very nearly topples down the stairs, but at least he does manage to stand up and take several steps. Ford gives a silent sigh of relief.

"Yes, that's how you do it! You… never did this before, did you?"

"Lemme think…" Bill pauses, and frowns. Well, Ford's face does. It feels surreal, watching himself from outside like this, and… and… is his nose always that red? "Nah, don't think so. No one let- huh, never actually got a buddy who'd let me borrow their meatsack. I mean, body. Yeah. Body."

Ford blinks. "Oh," he says. "But I thought, that with all the minds you inspired…"

"Geniuses can be real sticks in the mud, Sixer," Bill says, repeatedly flicking Ford's nose while gazing in the mirror with clear fascination. "Would listen to all I had to say and they really liked getting all the glory, but me? Don't think they liked poor old me that much. Guess they feared I'd outshine them if they let me pilot their body. I told better jokes than most of 'em."

In a not too distant future, Ford will wonder how could he not realize he was being baited, how calculated each and every word was, aimed to use each and every of his own insecurities as leverage. Right there and then he just frowns at the thought of how plain unfair that was to Bill - and at the memory of the betrayal he felt when he realized that Stan had destroyed his project simply because he couldn't stand the idea Ford could strive to carve out a path in the world on his own, as his own person, no longer part of a matching set. His intelligence was all good and dandy as long as it meant he could benefit from it, but the moment Ford had wanted to use it for himself, he had sabotaged him in the lowest possible way.

"The world should know about you," he finds himself saying. "They should know how much you have done."

Bill laughs, and it's actually just a bit unnerving, because the voice is Ford's own, but he's never laughed like that in his life. "In due time, Fordsy. In due time. Let's focus on your work first. That's the most important thing. Now-" he trails off suddenly, and frowns before looking down at his - Ford's - stomach. "Hey. What was that? Did you eat a troll while I wasn't looking?"

"Huh? No, of course not."

"Something's grumbling."

"... Oh. I believe that's hunger. I didn't have breakfast, come to think of it. Or dinner. Or… no, I think I did have lunch, yesterday. Maybe."

"Oooh, right! This vessel needs nourishment!" Bill exclaims, and grins up at him. "Never tried to eat and drink as a person!"

Ford laughs. "Well, to the kitchen, then. There's a first time for everything!"

It is a bad idea.

Ford spends the rest of the day, once back in his body, in an emergency room - trying to explain a very perplexed nurse how he got beer in both of his eyes and whole chicken leg bone lodged in his stomach.

"Well. It was fun, though," Bill tells him later, glancing down at Ford's body on the operating table. "Chess?"

"You know, you could turn that surgery scar into a smiley face if you just added another-"

"Bill. No."

"Bill. What did I tell you not to do?"

"Add a scar to make a smiley face."

"And what did you do?"

"... Add a scar to make a smiley face."

The call comes one morning towards the end of July, but Bill only finds out that evening - when he gets into Stanford Pines' mind to find out he's not home. Or at least, not in his home in Gravity Falls: the home he's at is the old one, the one Bill has seen through old memories where Stanford Pines is never alone.

He is alone now, though, sitting on the lower bunk of a bunk bed in his childhood bedroom, elbows resting on his knees and face in his hands.

"Hey, Brainiac. You look like the Head in the lake chewed you up and spat you out."

Ford winces, and looks up. "Bill," he says. "I… wasn't sure you could follow all the way here. Sorry I left so suddenly."

"I've got a door to your mind, smart guy. Will be able to follow anywhere unless you leave your brain on the nightstand or get a metal plate in your skull," Bill points out before shrinking just enough to sit comfortably Stanford's shoulder. "So, what's the word?"

"... My father's not well."

Not much of a loss in Bill's opinion, but he gives Stanford's ear a sympathetic pat. "How bad?"

"Very bad. He has little time left. I… I already knew that, but I kept postponing my visit. I had so much to do. We had so much to do. And now that it got worse, he doesn't even recognize me. I came too late. He kept asking for Stanley, and he acted like I was a total stranger."

You shouldn't be here. Please, leave.

Bill chases the memory away. "Must suck. Got to see your brother?"

Stanford shakes his head, burying his face in his hands once again. "No. We don't even know where he is. Mom has been looking for him, but he's just vanished. In the end I took off my glasses and pretended to be him, so that dad could think…"

He trails off and stands up abruptly, causing Bill to fall off his shoulder, but he doesn't even pause to look: he just wipes his eyes beneath the glasses and speaks again in a husky voice. "I can't sleep in this room. I don't know why I bothered to unlock it," he says, and marches out without another glance behind, slamming the door shut. Bill stays behind for a few more moments, hovering in mid-air, then he frows slightly and lets his gaze wander across the room.

It is old, and dusty as only rooms that have stayed empty for a long time can be. He can kind of see where Fordsy is coming from, really. It makes only sense to keep its door firmly shut - a locked room for a missing brother.

Something in the back of his mind stirs, or tries to. Bill chooses to ignore it without even realizing as much.

It isn't long after that day that Bill brings up, for the very first time, the possibility of building a portal.

"I mean, you figured that out already - all the weirdness in Gravity Falls is due to that: the fabric of reality is thin. Easier to punch a hole there than anywhere else. It would give your answers and, what's better, lots more questions to answer. A whole dimension of weirdness, all yours to figure out, and… hey, Fordsy, pick up your jaw. Still following?"

Ford closes his mouth and clears his throat. "I… yes," he says, and moves a rook forward. "Do you truly believe it's feasible?"

"I don't believe anything, Stanford. I know things. Of course it's possible - for you, that is. You're weird enough to do it."

That causes Ford to blink. "I'm… what?" he asks, entirely unaware of what's going on in Bill's mind, behind the all-seeing eye that refuses to see, refuses to remember.

Perhaps it wouldn't be too crazy to think you might take it a few steps further. You're weird enough to do it - Irregular as I am, just as unfit for this world, but they can't see it.

Bill pauses, and for a moment he seems almost confused. "Smart," he finally says. "Smart enough to do it. Don't know where that came from."

Ford smiles a bit. "I thought you knew a lot of thin-"

"Clearly not this," Bill cuts him off, his voice razor-sharp, causing the smile to die on Ford's lips. Bill seems to notice, and shrugs. "Sorry 'bout that. Had a funny moment," he adds, making the chessboard disappear with a flick of his hand.

"I am sorry," Ford says. "I… shouldn't have teased you."

"Hey, hey! Seems fair - I tease you all the time. Don't worry about it," Bill says, and lifts his hands. The operating room disappears, and they are once again in the mindscape - only that it seems oddly empty, starry sky as far as eye can see, with none of the books and papers usually floating about. Another gesture from Bill, and grids rise all around them - grids filled with graphics, equations and instructions. On equation in particular catches Ford's eye, and he adds something to it - only for Bill to change what he wrote.

"This is something unlike anything else you've worked on - your world's logic doesn't apply," he points out. "But that's why I'm here. Remember what you told me to call you, Brainiac?"

He does. "A friend."

"And you meant it, didn't you?"

"Of course!"

"Perfect. Because this is how genius happens, smart guy - with a little help from a friend," Bill says, and gestures to something before them, something that looks much like an inverted triangle with a hole right in the middle. "Here's what the portal's gonna look like. You may need help to physically build it, though - four hands are better than two and I'm not of much help there. Know a guy who might help?"

Fiddleford, Ford's mind immediately supplies, and he smiles. "I believe I do, yes. I actually think you'd like him, and-"

"Whoa there, wait up. Can't tell anyone about me, remember?"

"He's trustworthy."

I am not.

"Hey, that's the rule. No telling anyone. If he figures out this work's not just yours, then he does. But let's keep this under wraps until then."

Plus, I kinda wanna find out how you're gonna explain the shrine thingie. You creep.

Stanford nods. "Alright," he says, and glances at the portal's outline before smiling a bit. "That's not going to land me in an emergency room again, is it?"

Bill shrugs. "If it's gonna land you anywhere, Sixer, it's among the stars."

This one time, he's not lying.

Thanks to a rather ill-timed accident with his lab assistant, Stanford Pines finds out the truth earlier than he should have - but not early enough. Her can shut down the portal, but he can no longer close the tear he's opened. It's not enough to get through, but it's the start of something that, much like Bill himself, cannot be stopped.

"... So, I take it the guy won't be joining us?"

All-knowing! All-seeing! All-powerful! You can be, too! I thought you were the smart guy. Just join up.

Bill scowls, but doesn't turn, so they can't see it. "He'll either wisen up and do just that, or disappear with his boring old world. Doesn't matter."

Still, when Stanford Pines goes as far as placing a metal plate in his skull to keep him out for good, Bill rages - because there is nothing, nothing he hates as much as being shut out of a place where he has every right to be. Stanford had no right to call off their deal. When the wayward brother returns to kick Brainiac through the portal, Bill puts out a generous reward for his capture across all of the dimensions he has indirect control over.

He doesn't really expect someone to catch him, and in fact no one does for the next thirty years. But it doesn't matter: all he needs to do is wait. They will meet again. He knows they will - and he knows that Stanford Pines will be very sorry he crossed him.