Mathématique: Intergalactic Gate Bridge

“Hey,” Rodney McKay snaps, a real edge in his voice, because he believes this. He does. “Science, done with low blood sugar, ends lives.”

Chapter warnings: Stressors of all kinds. Grief. Physical injuries. Mental health challenges. Panic attacks. Memory loss.

Text iteration: Midnight.

Additional notes: None.

Intergalactic Gate Bridge

Rodney McKay wants Sam Carter. He just does. And yeah, he’s talked about wanting her, even if only to himself, ever since he heard about that insane, glorious, genius, brilliant, sparkler of an idea: the way she’d passed an asteroid through the Earth by putting it into hyperspace. Saving the day while respecting momentum. Like all the best physicists know how. He’d felt the strength of her theory and the skill of her praxis from his cortex to his toenails. Before he even knew what she looked like or had heard her speak, he’d developed an entire combative love/hate relationship with her in his own mind. And then. And THEN. She’d had the nerve to be gorgeous. Smoking hot. By anyone’s standards. That’d been distracting. For years. Maybe a decade. Maybe a decade and a half.

But now, striding through the Odyssey’s corridors like he built the place (and, yeah, he contributed), he just wants her. Not sexually. Not romantically. He just. Wants her.

He wants her because everything is falling apart, and she can always, always fix it. Every time. Without fail. That intellect of hers burns like a torch. Not brighter than his, but steadier. More confident. She believes in herself in a way he’ll never personally know or understand or feel. Not in this universe, anyway. Other people believe in her. Without question, without fail, they just believe. And why wouldn’t they? She’s saved everyone. Over and over and over again.

She can save John, if Rodney can’t, because she can do anything.

Not that he’ll admit that out loud.

Something’s happening to John, to his mind. Something’s happening to Nick Rush as well, maybe something more and worse, and maybe—maybe something faster. Rodney’s not sure yet, he doesn’t know, but occult knowledge of Ancient tech is never good; Rush has opinions about the sound of a language he’s never heard spoken, and John’s been going deeper into the city, deeper all the time. Rodney’s started mapping his runs, the way they spiral in huge arcs, like ballistic trajectories around a center of mass. As though he flings himself out, away from the place he wants to go, and as though it pulls him back with mental gravity.

The chair.

That’s what John’s ballistic runs arc away from, fall back towards.

And there’s no one for Rodney to tell, other than Jennifer Keller, who, as much as Rodney adores her, comes up with gently delivered observations along the lines of: “Rodney, he’s going through a tough time right now. Maybe he just likes going for runs.”

Elizabeth would have understood. She would have seen the problem immediately. The way it centers on the chair.

But Elizabeth is gone.

And, yeah, sure. He could tell Woolsey. Maybe he will. Any day now.

Elizabeth would have understood. She’d have understood not only what McKay was saying, but how he was saying it. She got him. People don’t get him. It’s rare.

His throat hurts.

Is he getting sick?

He has a headache.

 Maybe it’s just the lights on the Odyssey. The whole place is brighter toned than the Daedalus. It doesn’t feel like home. Nowhere feels like home anymore, except Atlantis. Probably nowhere ever will.

Rodney sighs.

Atlantis doesn’t love him the way that it loves John. But it’s learning to see him, all the same. He has the gene. Artificially gifted, sure. But Atlantis knows his hands, the tread of his boots. Over the years, control panels have begun to come away easier and faster. Chimes penetrate his mind deeper with each passing season. He can, almost, hear the shield when it’s active. A subsonic pressure against his skull. Bone conduction.

He’d told John he was going to eat. 

He is, maybe. But first, he’s going to find Carter. She’s gotta be out of that Top Secret Colonel Meeting. Where would she go, on a ship like this? Where would he go if he’d just wasted an evening storming a building and there was science to do? 

Back to his lab.

And so. The transport room. Back to Earth. Almost certainly, that’s where she’ll be.

So that’s where he goes. 

McKay walks through Cheyenne Mountain like dropping in on the High School Varsity Chess Team that first semester home from college. And yeah. Turns out he forgot the Milky Way folks work under a pile of dirt. Literally. It’s a pile of dirt. Right over. His head. God, he misses Atlantis. Like an ache in his teeth. It hurts more when he bites down on it and so of course he can’t help himself. He closes his jaw. It’s what he does. Has he always been like this? 

He barely remembers himself, ten years gone. Exactly the same. Wildly different.

He rounds the door to Carter’s lab, and yup, sees her sitting there, back to the door, bent over—huh. What is that? It’s a got a whole mess of capacitors. That’s about all he can say from the doorframe. She’s changed out of her unbelievable blue pant suit. Who picked that for her? With the curves she has, that suit was a crime. And her eyes had looked so blue. She’s in fatigues now. That’s better. Less electric. More grounded.

He’s still in his James Bond suit. He feels ridiculous, dressed like this. He should have changed before coming.

“Colonel Carter,” he says to her back, like he’s announcing the name of his arch nemesis. “We haven’t really had the chance to talk about the Gate Bridge thing, what with all the rushed undercover ops. No pun intended.” It’s overly formal. Why does he do this? Can’t he just say, Hi Sam, like a normal person?

She doesn’t turn around. But she does, very gently, set down the tiny jeweler’s screwdriver she’d been using.

This doesn’t—um. This doesn’t sit quite right with Rodney, but he powers ahead. Because that’s what he does. Powers things. Along vectors.

“I, uh, I wanted to explain,” he begins, because, yeah. He really does. Except for all the ways he most certainly does NOT. Maybe if she were looking at him, extremely kind, slightly impatient—he might get it out. But nope. Okay, it’s not happening. Which is fine, he has a plan B. “About the Gate Bridge. I wanted to explain about the Gate Bridge. It was an issue of security.” He hears the didactic note in his voice. He hates it. He needs it. He won’t be stripping it. “It was a—requirement. I can’t get into the specifics—just know I didn’t make the decision lightly.”

He wishes he didn’t remember what it felt like to run through the hallways of Atlantis in the middle of the night, screaming John’s name.

“It’s fine,” Carter says, short and forceful and still not looking at him.

She’s not even going to turn around?

“Well, um, good,” McKay says, off balance, trying not to show it. “We should—we should talk about—we should make a plan, or at least make a timetable. We should— Could we—” He stops. He regroups. He starts over. “The Gate Bridge needs to be restored. This should be a top priority. For us. For you and me.”

“Not now,” Carter says. “It’s been a long day. We’ll talk in the morning.”

“We’ll talk in the morning?” McKay echoes, indignant, incredulous, inveterate.

Because since when. Do they. Talk in the morning.

McKay can’t remember the last time he had the luxury of “talking in the morning,” and yes, sure, Carter is correct, they could have this conversation in the morning, after he’s eaten and slept and tried not to choke on the dust that’s accumulated in his apartment—but he doesn’t want that. Because he didn’t come here to talk about the Gate Bridge. Not really. He came here because—

Because—

Because—

He’s unnerved and he’s frightened and he’s alone with it because as miraculous as John manages to be on a regular basis, as smart as Zelenka is, as much kindness as Keller has, as much grit as Teyla brings to bear, and as much, uh, Rononness as Ronon shows up with on a daily basis, they don’t have to keep literally everything literally glued together with their literal goddamned hands. Like he does. Like Carter does. Everything just seems so hard. So hard and so frightening and he’s mapped the edges of his own limits, he’s seen them contract and reexpand, and he doesn’t like it and there’s only one person, one person he’s ever known his whole life long, who always, always knows what to do and—

“Will you JUST TURN AROUND?” The fray in his own voice is like static over signal. His eyes are burning. He wants her to turn. He needs her to turn.

She does turn.

Her face is a mess.

She’s been sobbing into her capacitors.

Sobbing. For sure. The kind of full-body cry McKay has only done four or five times in his life. Her face is red, her nose is running, her eyes are streaming, and her whole body is hunched, one hand pressed to her sternum, like it hurts her.

And, oh. Right. He’s sure it does. It must.

“Are you HAPPY NOW?” she snarls, real anger beneath those tears.

Um, no. Not really.

“What do you WANT from me, McKay?” She shouts it. She shouts it, like he’s come to torture her.

And god. Maybe that’s—maybe that’s not so far from the truth. McKay swallows hard. His throat aches. That’s all he seems to do to most people. Torture them. Try them to the end of their patience, while they’re forced to tolerate him because he can split atoms, seal microfissures, manipulate pressures, and calculate those long beautiful arcs of ballistic trajectories—all by hand, if need be. Often, that’s what it comes down to.

“Get out.” Her voice is hard, thick with tears.

He almost does it. Almost turns on his heel and leaves her in peace. Because she won’t tell him it’s going to be fine. She can’t. Not tonight. For some reason, that’s the thing that sends him over the edge. Not John and the round from Telford’s gun he almost took to the head. Not a memory-free Nick Rush, cut open, unaware, wielding knives. Not his own fears or ghosts or failures—no. The thing that takes out Rodney McKay is Samantha Carter, losing it, alone, to a hand-built array of capacitors. 

“If you’re gonna cry,” McKay says, fierce with his own tears, “you cry over crystals. Not capacitors.”

Carter says nothing.

“Go ahead.” McKay sniffs. Wipes his face. “Ask me how I know.”

“Okay,” Carter says, all whisper and fray, like she’s been sobbing her glorious little heart out for minutes and minutes on end and has no voice left to speak with. “How do you know?”

“You get saline between your plates and your dielectric one time and you never do it again. Especially if your plates are millennias old and keeping a biohazard containment field in place.”

Carter sobs a laugh, then wipes her nose with her sleeve. “Yikes.”

“Tell me about it.” McKay takes a step forward. A second step. A few more. Then he’s peering over Carter’s shoulder, tears still forming and going their way with a predictable frequency. He wipes his eyes. “That a matter-wave infrerometer?” 

“Yeah,” Carter says sadly, her hand pressed to her chest. “Part of one, anyway. I was trying to give it a better life.”

God, does she really think like this?

Of course she does.

That’s what he hates about her. That’s what he loves about her.

“A better life?” McKay sniffs. “Sounds nice.”

“I don’t get to do much inventing,” she says. “It’s mostly fixing. You know?”

And oh god. He knows. He knows like current ripping through resistors. And what the hell is wrong with him?? Rodney McKay has grown as a person, and it’s terrible. He hates it. Hates it deeply. This is why he’s cultivated his whole persona! It’s so he won’t have to feel like this. Because that’s the difference between them. He’s a fixer. He wishes he wasn’t, but he is. That’s his nature.

But she—she’s not.

Samantha Carter is a generator, burning incandescent and hot, wedged into a space that only sometimes makes room for her. 

Where the hell is her team? Huh? Answer him that. Where the hell is Jackson? Vala? Teal’c? The Other Guy?

Jackson has some kind of plague.

Vala’s in surgery.

Teal’c took a bullet through the arm and somehow went to a secret briefing anyway.

Other Guy has zero excuses McKay can see.

“I know,” he says, pretty sure she’ll kick him out any second here, and he wouldn’t blame her, because he generally doesn’t do things like this mostly because he’s REALLY BAD AT THEM. He only does them for John, because John gets him, gets what he’s trying for and takes that to heart, not what McKay actually executes on, which is always lesser, always shifted in its wavelength after passing through that almost infinite wall of potential energy that constitutes the persona McKay started building for himself circa age eight, when he’d been told he played the piano technically, mechanically, and without a shred of heart.

“I know you know,” Carter replies.

Could she think he’s like her? When he’s vertical kilometers below, still in upper atmosphere, always looking up at her Kármán line?

Gingerly, McKay sits across from her. He pulls up a stool. The height of the lab bench and its black resin surface is achingly familiar, terribly foreign. “So,” he says, trying for businesslike, missing by the length of a Daedalus-class starship. He hooks the heels of his boots over the lower rung of his stool. “What are we looking at, here?”

“I’m experimenting with phase-shifting,” Carter admits, reluctant.

“That much I can see.” McKay summons the hint of an edge beneath his shattered astrolabe tone, thank god. “What are you trying to make?”

“A device that shifts the phase of a matter wave in an adjustable, analog manner.” She rubs at her neck, where McKay sees the upper edge of a bandage, the kind they use for burns.

“Adjustable,” McKay echoes.

“They’d all have to do this,” Carter says. “Every culture who’s developed phase shifting technology—they’d have to start this way.”

Would they? McKay pauses to consider this, hunched over the pieces of Carter’s creation. It’s electrostatics that keeps things from occupying the same spaces, and gravity that holds one to the surface of whatever planet or mass one happens to be standing on. So, when one eliminates electrostatic repulsion (or, “interference,” when one’s talking about waves) one should really end up sinking through the floor. However, every device the SGC has ever encountered that allows phasing through objects doesn’t send people toward the center of the Earth at 9.8 meters per second per second, which means there’s some safety mechanism built into the tech itself. And that safety mechanism would have to be relational to applied forces or marry electromagnetism and gravitation in some way, and—

That’s really interesting. She’s right.

“Go too far too fast and you’ll fall through the floor,” McKay says.

“The sweet spot,” Carter replies, “I think, can probably be found by starting with very small adjustments in phase. Unnoticeable at first, but titratable. So you can very slowly work up to the point where, say, you can, if you try extremely hard, force the blade of your hand—” she mimics a slow-motion karate chop, “through a thin, solid object. I was thinking plexiglass?”

“Whoa, slow down, Luke Skywalker,” McKay says.

“Yeah, okay, probably first plexiglass through plexiglass, then a tissue equivalent through plexiglass, then my hand through plexiglass,” Carter says, with a small smile.

“Yeah, or, y’know. New Guy’s hand,” McKay shrugs. “Just a thought.”

“Mitchell,” Carter says with a small smile. “He’s coming along. Showing real promise.”

They look at one another. 

“Any chance you want to get dinner?” McKay asks the woman who wants to pass her hand through plexiglass. “Not—not as. I mean. I’m just hungry. We could see what’s in the vending machines.”

Carter does a little half roll of still wet eyes. “I should really—” she trails off. And then her expression is breaking all over again, like all the things she should do have started splitting her to the bone. That hand is still at her chest, pressed over her sternum. This close, McKay can see her pressing hard. Pressing down. Like she’s testing the integrity of bone and sternal wire, like she’s wondering if maybe—

“Hey,” Rodney McKay snaps, a real edge in his voice, because he believes this. He does. “Science, done with low blood sugar, ends lives.”

Carter, startled by his ferocity, stops trying to crack her own chest open.

“Sure. It’s past midnight,” he continues, “but I guarantee you there’s a place in this city where we can get Real Earth Food.” McKay’s going Full Scientist. “We will find that place, and we will eat at it.”

Carter goes Full Eye Roll, but McKay doesn’t care.

They decide on O’Malley’s. Turns out, the guy who owns the place has, over the years, come to a tacit understanding that SG-1 has saved the world a time or five, so he’s willing to fire up the kitchen when Samantha Carter calls.

They take the elevators to the surface and emerge beneath a familiar night sky. McKay looks up to see all his old friends, glittering against the black. Vega. Altair. Arcturus. The constellation Pegasus vaults across the canopy of the dark. He sees the Milky Way, edge on—a band of dust splitting the planar smear of stars.

“Miss it?” Carter asks.

“I’m not sure.” McKay reaches for clarity and comes up with nothing except the way the starscape, seen from Atlantis, had confused him in those days of failing memory, how this view of his home galaxy, seen from below, was, somehow, what the oldest/youngest parts of him expected to see.

Carter, also looking up, says softly, “I understand that prolonged proximity to Ancient technology has—effects we don’t talk about.” Her blonde hair is awash with starlight and moonlight and fluorescent parking lot light. All of it reflected. It doesn’t seem right that she doesn’t glow from within.

“If,” he says, deadly serious, “one day, you tell me you’re an Ancient, I won’t be surprised.”

She takes it like a joke, giving him an oh-come-on smile, like she doesn’t remember standing with him, wearing a pink track jacket in a sinking jumper, begging him to wait for John Sheppard. Not to waste his power. Not to waste his air. He’s never asked her about it. He won’t now. But he doesn’t laugh.

“I’m not an Ancient, Rodney.” She lets her amusement go.

“The thing is,” McKay replies, his voice soft, serious, “that’s what they all say.”

She looks at him with those blue eyes, dark and wide.

“You’re wise,” McKay says. “In the ways they are. Were.” He stops there. He doesn’t tell her that she feels like Atlantis feels to him—bright and kind, generative and receptive, adaptable and alive. Lonely.

“Thanks, Rodney. Can you tell me your sister’s name?”

“Um, why?” he asks.

“Because I’m gonna need to verify you haven’t been replaced by an alien entity.” There’s a hint of mischief in her eyes, but just as much concern.

“Jeannie,” he says, sighing. “But all the alien entities I’ve encountered that can suppress someone’s consciousness can also extract information from memory. So.” He shrugs.

“It’s more of a mixed bag in the Milky Way,” Carter says. “I guess I’ll take my chances. Come on.”

She leads him down the sidewalk and stops in front of—

“No,” McKay says.

“What?” Carter asks innocently, unlocking what appears to be a restored vintage motorcycle. She tosses McKay her helmet.

He catches it. With difficulty. Not suavely. “I take back literally everything I said,” McKay snaps. “You ride a motorcycle?”

“And I do it very well.” Carter straddles the bike. “Come on, Rodney. You’ve done things that are orders of magnitude more dangerous. Didn’t you try to exact vacuum energy from standard spacetime?”

“Yeah—but not for—for—leisure,” McKay sputters.

“You just told me low blood sugar science ‘costs lives’. This food is important.” Carter has the audacity to grin at him. “Live a little, McKay.”

There’s no one else in the universe for whom Rodney McKay would mount a motorcycle out of aspirational camaraderie. But this is Samantha Carter. And, together, they’d built a Gate Bridge. He’d reached for her across the intergalactic void. She’d reached back.

“C’mon.” Carter starts the engine, eases the bike out of the space where she’d parked it, and points it along the vector that will take them out of the parking lot. “You can hang onto me. O’Malley’s is just down the road.”

“I know where O’Malley’s is,” McKay mutters. He jams a too-small helmet onto his head and slings a leg over the bike, against every fiber of his better judgment. “Where do I put my feet?”

Carter, a little sly, points out the footrests. “Scoot forward. You can hang onto my hips.”

“Okay,” McKay says, glad she can’t see his face, which feels like it’s doing something awkward. “I—” But Carter takes off. McKay tightens his grip. “A LITTLE WARNING WOULD BE NICE.”

“Just relax,” Carter says, loud over the bike’s engine. “Forward momentum is stabilizing. Lean into the turns, not away from them.”

“I understand momentum, thanks!” McKay tries not to dig his fingers into Carter’s hip bones and does his best to keep at least a little space between them because this is really not how he thought his night would go, and he’s mostly over his, er, decades-long immature crush on Samantha Carter BUT there is only so much a guy can be expected to take and literally hanging onto Carter’s hips as she directs a motorcycle down a dark and winding mountain road is going to feature heavily in his thoughts for the rest of his life and there’s really no getting around that, unfortunately.

They don’t talk over the sound of the bike and the rush of the wind. Carter keeps the pace smooth and even and without surprises. They lean, together, into the turns. He learns how to adjust his weight to stay with her. To help in all the ways he can.

The experience is bone-shatteringly glorious.

He tries to enjoy it. Just—not TOO much.

To give the whole thing the right reference frame, the best reference frame, he thinks of their line of stargates, stretching 3 million light years through dark and through cold, where virtual particles blink in and out of existence in fractal quantum foam he’ll never see. He thinks of how much he loves Carter, not sexually, which is the easiest way for him to talk about, but conceptually, platonically—all the ways he wants the best for her. How he’s, slowly, with time, learned to value those local maxima—those best possible outcomes—for himself and for others.

It took what happened to Elizabeth, who he will also, always, deeply love, to understand how unfair life can be and how valuable it is to live well. How valuable it is to die well. How he, himself, had nearly died in the cruelest of ways. How his friends had, with all the best intentions, found a way to make a cruel death an excruciating one.

He’d understood, in that cave, in the rain, John’s tragic talent for such things.

And yet.

Here he is.

He’d survived, against all odds, to ride a motorcycle with Samantha Carter, under stars. His whole self aches with it.

When she parks the bike in front of O’Malley’s, McKay has something he’ll carry with him forever, as long as he carries memories at all. He unbuckles Carter’s helmet and hands it back to her. She takes it without speaking. Her eyes are red again. Space Allergies making the rounds.

Then again, it was a ride full of wind, and she’d had nothing to shield her face. 

“Thanks,” Rodney says, and not for the helmet.

“You’re welcome.” Carter locks the bike, and two physicists walk into an empty bar.

Carter orders a burger and an amber ale. Rodney orders half the menu and tells the owner he’ll make it more than worth his while. For the first hour, they cruise through safe topics: matter waves, quantum chromodynamics, information architecture, securing intergalactic transit mechanisms against America’s Most Dangerous Cryptographer. Carter orders a second beer. Rodney follows suit. Conversation shifts into riskier territory. Time dilation. Variant selves. Mind and memory. And—

“You don’t have to answer this,” Carter begins, almost done with her second beer. “It’s a personal question.”

McKay swipes a fry through ketchup.

“Never mind.” Carter chugs the dregs of her glass.

“Ask it,” McKay says.

“Maybe an observation, instead.” Carter looks down at her plate. “You and Sheppard.”

A terrible weight lands on McKay’s chest. “That’s it? That’s the observation? ‘Me and Sheppard’?”

“Yeah,” Carter says gently. “That’s it. Except—does it bother you, either of you, when people call you McShep?”

“Why would it bother us?” McKay asks, already understanding what she’s driving at.

“Oh I don’t know.” Carter’s face crumples. She tries to hide it, wiping her nose on her sleeve, chewing a fry she can barely choke down. “Just thought it might. I— One time— One time I had someone—without having them at all, really. Can’t say I recommend it.”

McKay’s throat closes. “I—” And yeah, that’s not happening. He takes a breath. Recenters. “Anyone who would let you go is a pile of garbage.”

That surprises a laugh out of Carter. Sharp and real and cutting through her tears like the slice of aircraft through rainstorm.

“Your Pile of Trash,” McKay says, fighting down every emotion he has. “Jack O’Neill?”

“I hate that everyone knows,” Carter whispers. “And he’s not a trash pile. He has competing priorities. Together, we made half the axle that kept the planet safe. For a while.”

“Yeah, well, I’ll give you most trash piles haven’t saved the galaxy scores of times. But he’s still a pile of trash. Ask me—” McKay’s voice breaks. “Ask me how I know.”

“You’re in love with Sheppard?” Carter struggles to get the words out.

McKay can’t look at her. Even if he could, he wouldn’t be able to see with all the salt working its way out of his eyes. But it’s important that she understand. He shakes his head.

He can feel the shift in energy as she realizes what he means.

“He’s in love with you,” she whispers, realtime revelation.

He nods, white-knuckling his way through this, wishing there were tech specs to check on his own personality. “Yeah. Yep. Yep, I’m pretty sure.”

“But you don’t—” Carter breaks off, heartbroken. “You don’t feel the same way?”

And if McKay’s possessed by anyone tonight, it has to be the spirit of Jack O’Neill—a metaphysical passenger he doesn’t want and probably has nothing in common with, other than, maybe, a non-romantic yet total adoration for Colonel Samantha Carter.

“I’ve spent entire lives searching for him,” McKay confesses. “In alternate universes.The ways that man gets himself lost—” His voice breaks. “The things I’ve done to bring him home. It’s gotta be that sometimes we find each other in the right ways. Across the multiverse.”

Carter looks at him, her expression agonized. “Why not this one?” she asks. “Why not this universe, if you care for him so much?”

“Because,” McKay says, “John Sheppard is more than half in love with Atlantis itself. It gets him into trouble. It takes him places I can’t follow. I don’t know how to weigh myself against the spirit of a living city. A dead culture. Can I? Should I? I’d have to work to get my sexuality to fall in line. I’d have to work hard. It might be worth it. But—”

This brane of the multiverse has Jennifer Keller living on it.

She flashes into his mind: standing in a cave, backlit by a late-afternoon waterfall, deep in Wraith territory, holding a drill. Brave and frightened. About to try something impossible. About to succeed.

“But?” Carter echoes.

He wonders if O’Neill has his own version of Jennifer Keller. If he does, Rodney McKay will never know. Doesn’t want to. But it must be something—because only a massive, perfect storm could keep anyone away from Samantha Carter. 

“If the Pegasus Galaxy didn’t depend on the structural integrity of ‘McShep’ as a construct, I might try to move past my personal hangups,” McKay says. “But you know me. You know how terrible I am. You’ve said it yourself. Nine universes out of ten I screw it up and everyone dies.”

She gives him a look, but she doesn’t deny it.

And she shouldn’t. He is terrible.

With people.

With tech, he does just fine.

“Aren’t you lonely?” Carter asks. “When you go home? After you’ve blown up the star, taken out the enemy fleet, rescued the amnestic cryptographer? When no one goes with you? When no one’s there, waiting?”

McKay thinks about stumbling back to his quarters, drunk with fatigue, looking up at the geodesic shimmer of the shield against the night sky, falling into bed, and hearing, as he loses himself to sleep, faint chimes. F major. The Key of Joy.

“Where’s Mitchell?” He asks as gently as he knows how.

“With Carolyn Lam.”

“Ah.”

There’s a long silence.

“Does it seem to you,” McKay begins, “that the longer you live, the harder life gets?”

Carter nods without speaking, her eyes full of tears that aren’t quite ready to fall.

“I thought it would go the other way,” McKay confesses, cracked voice. It matches his expectations.

“Did you?” Carter whispers. “Optimistic.”

“Not a trait I’m known for.”

“Well,” Carter gives him a wan smile, “angry people are usually hopeful. You’ve gotta have hopes for them to be unexpectedly crushed.”

“Dark,” McKay says, swiping another fry through ketchup, but not quite able to eat it. “Probably true.”

“Daniel pointed it out to me.” Carter looks at the bottom of her empty glass. “Years ago. Before he—” she breaks off. “Daniel doesn’t get angry anymore. Not like he used to. That old, hotheaded indignation is mostly gone. Except—” Carter breaks off, smiling faintly. “Except, sometimes, Vala can bring it out.”

McKay eats his fry.

“Jack didn’t have anyone,” Carter continues. “We used to spend time together, after missions. The intense kind, where you didn’t want to go back to a set of empty rooms. Sometimes he’d sleep on my couch.”

“Hmm,” McKay says. “Well, speaking of your couch, my apartment is long gone.”

It’s not.

But he can pretend for the night.

“You need a place to crash?” Carter’s face is tragically hopeful. “I hear good things about my sleeper sofa.”

“I’m the harshest critic you’ll ever find.” McKay finishes his beer.

“Don’t I know it.” Carter wipes her face. 

Outside, before they get back on Carter’s motorcycle, they stand beneath the night sky.

She holds out her helmet.

He doesn’t take it.

“Do you think we’ll be okay?” McKay asks.

She looks at him for a long time, her eyes searching his face. She doesn’t say anything. She lowers her helmet to her side.

“If you’d said yes,” McKay whispers, “I would’ve believed you. You’re the only one I would have believed.”

Carter looks at him, and for all her sadness, for all the nuanced layers of her understanding of who he is, and what he means—she might as well have been John Sheppard. He might as well have been Jack O’Neill.

And, in this precise moment, he knows what he gives John that lets the man do everything he does. 

Because it’s the same thing O’Neill gave Carter.

The thing she doesn’t have. The thing she’s been missing. Maybe since Jack O’Neill left the Mountain.

Someone who sees her. Sees what she does, how she does it, all the ways—

“Sam,” he says, urgency rising like a charging capacitor. “I believe that you can do anything. I believe—I believe—god.” He’s tripping over himself trying to get the words out, the idea across, already worried he’s too late. He might be months too late, even years too late. “You’re borderline magical. It’s it’s it’s it’s obscene, actually. Everyone talks about Jackson, it’s always Jackson, he opens doors, sure, but you—you build windows. You get overlooked. The creative capacity you bring to bear is is—it’s beyond belief. Beyond rational credulity. The physics you do—it’s—it’s full of—”

It’s full of joy.

But he can’t tell her that. He can’t tell her it’s full of joy and he can’t tell her it needs to stay that way. That humanity’s continued survival almost certainly depends on it. He does that, and it’s like putting an orchid in front of an ion canon.

Maybe O’Neill understood as much—how tenuous, how necessary Samantha Carter’s joy was to the survival of humanity. Maybe that’s why it didn’t work out. Maybe that’s why he’s not here. Because, in the end, he couldn’t make her happy, and he knew that.

The insight is crushing.

“Rodney—” Carter looks perplexed. “What’s gotten into you?”

He’d like to charge up that old Samantha Carter fire, any way he can. But Rodney McKay—he’s no generator. 

He’s a fixer.

And part of his particular genius involves knowing exactly what he can and can’t achieve.

He lets his urgency dissipate, bleed into the night air. 

“I don’t know,” he says, even though he does. “It’s been a rough year or five, I guess.”

“You okay?” Carter asks.

No, definitely not.

“Yeah,” he says.

He’d started the night wanting her. Not wanting her sexually, but wanting her the way a scared kid wants a flashlight. Or a parent that was worth a damn. He’d wanted her to tell him everything would be all right. That she can help him help John. That she’ll always be here, on this side of their Gate Bridge, holding the near bank.

“What happened,” Carter asks, with plasma-torch insight, “that you felt it necessary to tell John Sheppard how to access our Gate Bridge?”

“I didn’t think I’d be there anymore,” McKay confesses, looking at her. “Our back door—it was for emergencies. For you and me. I didn’t want—” He pauses. Gives up. Starts again. “I wouldn’t leave you alone on this end.”

Carter gives him the kind of smile she probably gives Jackson every day. All the time. “Thanks, Rodney.”

“You asked me if I get lonely,” McKay continues, looping back to a conversational thread she’d probably thought he’d dropped. “When I go back to my quarters, at night, alone, after missions. And I am. Of course I am. The bigger the effort, the worse the let-down.”

“Yeah,” Carter whispers.

“Here’s the thing though, Sam. From my room, I can see the stars. Don’t tell anyone this, but I actually picked my room on Atlantis so that, for the majority of the year, I can see along the vector that would connect Pegasus and the Milky Way. At first, it was—I don’t know. Call it nostalgia.”

Carter nods.

“Funny thing though,” McKay says. “Since our Bridge went up, every night, I can’t help but think of all those gates. The program we wrote to link them together. The way it must actually look when it’s active, if anyone could see on scales so vast.”

“Spacetime arcades,” Carter whispers. “Like ancient Roman aqueducts. You look along the directional vector of the McKay-Carter Intergalactic Gate Bridge? Every night?”

“Try it sometime,” McKay says, quietly.

Carter smiles, looking up at the stars, at the constellation Pegasus. McKay moves to stand behind her, pointing, one hand gently torquing one of her shoulders. She shifts, to follow his line of sight. “A little to your left,” he murmurs.

“And straight on ’til morning?” Carter asks, with a hint of that vanished spark in her voice.

“Recta usque ad mane?” McKay repeats. “Motto of the Lantean science team.”

“Shut up,” Carter says, with a flash of teeth, a real grin this time. “It is not.”

McKay shrugs airily, then pushes the helmet away as Carter tries to offer it to him. “Come now. Our brains are of—hmm, roughly equal value? It’s only fair that the risk be distributed.”

She puts on the helmet. 

They get on the bike. 

And all the way down Cheyenne Mountain, Rodney McKay feels the wind in his hair.