So.

When I started this, I said that this fic takes as canon until only the events up to Season 4 of Agents of S.H.I.E.L.D.

I never said anything about characters or locations that have appeared in later seasons. ;)

My excuse is that those characters, those locations do exist somewhere out in the world, even if they haven't been explored. The Lighthouse (from Season 5) remains an example, as you've seen in the last chapter.

Other - hmm, let's call them elements - might also make an appearance down the line. ;)

Thanks to my beta, ElessarII, who had the patience to go through this chapter and actually like it. Wow. You're an excellent ego booster, my friend.

[02.01.2021] EDIT: I've overhauled this entire arc to better fit where I'm taking this story. Old readers - apologies for the inconvenience. New readers - hope you enjoy the story.

Let me know your thoughts in the comments down below.

The world was void,

… A lump of death—a chaos of hard clay.

The rivers, lakes and ocean all stood still,

And nothing stirr'd within their silent depths;

- Darkness, Lord Byron

TIME: UNKNOWN

LOCATION: UNKNOWN

"You nap any longer; you're gonna lose a hell of a lot more than five years," is the first thing she hears when she comes to.

She pushes herself on shaky arms, breathes through the nausea, and immediately chokes. It doesn't feel like that's oxygen that's going into her lungs - feels like sand.

Isabelle scrambles away until her back hits a hard, rough surface. Rock, her probing fingers tell her.

She's been hit on the head enough times in her life to recognize the symptoms of a concussion by now. Her head's pounding, and there's a muted ringing in her ears. But concussion-induced hallucinations are rather rare, Isabelle reminds herself as she stares at the huge black hole in the sky, an aura of light seeping into it.

The whole of her right side is numb. She looks down and is concernedly unsurprised to find a ghastly patchwork of red and charred black where pink, healthy skin used to be. The water from her suit must've repaired as much as it was able to keep her alive.

Any other day, she'd be screaming at the sight. But if the voice that had woken her up hadn't elicited such a reaction from her, she doubts anything would.

"If it makes you feel better - looked a whole lot better than mine did."

She looks to the devastatingly familiar figure casually leaning against a rock, legs pulled up to his chest. He wiggles his fingers at her, and her gaze gets caught onto the rough, aged yet unblemished skin of his own right arm, which had been a dark, shattering reflection of hers the last time she'd seen it.

"You're not real," she says. The water hadn't bothered healing her crisped nerve endings, so she doesn't feel pain anywhere - for now - but it can't do much against the black hole in her chest, mirroring the one in the sky.

So much for hallucinations being rare.

Tony Stark's mouth curls up in an asymmetrical smile. "How do you figure?"

You mean, besides the obvious?

"Hoodie's too clean," Isabelle murmurs nonsensically, her eyes fluttering shut of their own accord until all she can see is the faintest glimpse of the orange piping trailing down a grey-black hoodie. There's no sign of the black, powdery substance that seems to permeate every inch of this macabre fantasy her mind has come up with.

She jerks as he kicks at her leg hard. "I'm the only thing that's not really here, Izzy," he says emphatically, surprising no one with his ability to read her thoughts.

Her spinning, aching brain splits that incomprehensible sentence into individual letters then puts it back together again as words that are scrambled all over the place. It takes a good long while for the meaning to finally sink in, and by then, Isabelle's too tired to doubt his words.

Her eyes rove over the landscape. The surface is barren and cracked as far as she can see. Even the mountains in the distance are just as black and dead, with not a single sign of life. "Where am I?"

"Very, very far from home."

Until now, she'd been the only member of the original seven Avengers to have never been on an alien planet, or even to space.

She's not missing a whole lot.

Her fingers curl into the ground, feeling the way the black substance gives beneath her hands.

"Not sand," he says. "Not soil. Ash."

"Ashes of whom?" She tries not to breathe too deeply, then remembers that it makes no difference either way.

Tony shrugs. "Nobody. It's just what this whole planet is made of. Well, I call it ash - the actual term would be dark matter particulates. But ash is more dramatic, don't you think?"

"Drama was always your thing - are you gonna stop kicking me?!"

"Don't fall asleep, and I won't have to. What's the last thing you remember?"

She groans but shoves her mind to where he wants it to go. No version of Tony had ever let her be at peace when he wanted something. Brat. "The ocean," she says, tossing out words as memory slots into place. "Dark, and cold."

She shudders out a breath. "I killed someone. A woman. And then, I fell."

There's silence for a long moment. "What do you feel?" His voice is soft.

"Burned out." She slumps sideways into the ash. "Please, Tony. Let me rest."

"You can't. Not here."

"There's no water table," she murmurs, not having consciously realized it until the words escaped her mouth. "Whole planet's barren. Even if I sleep, I won't lose control. I won't hurt anyone."

There's silence for a long moment.

"Not that you'd care even if you did."

That tone - disdain mingling with disappointment - perfectly synthesized to yank her back from the abyss. Despite herself, she cracks one eye open. "... what's that supposed to mean?"

Tony shrugs, eyes piercing exactly the way they had in life. "You've never been much for family. You abandoned me half my life, lied to me, betrayed me willingly. You stole a Time-Space GPS just to get away from that burden. You still have it, don't you?"

Isabelle knows what this is. She does. But it still feels like being punched in the chest. "Shut the fuck up."

"You've wanted this ever since I died. Pushing yourself so hard, hoping your body gives out on you so you don't have to go on. You never even wanted to come back."

"Stop it."

"Let's be real, Izzy," he snaps, pushing himself to his feet. Her stomach clenches at the look on his face. "You've exchanged - what? A dozen words with my daughter? You abandoned Pepper and Rhodey and Peter. You don't give two hoots about hurting people. You won't even care if they died."

"I said shut up!" Within the span of a heartbeat, she's upright and launching herself at him.

Her hook is too wide; he easily evades it. But the lack of a real, physical jaw snapping beneath her fist doesn't foil the sudden bolt of agony that screams down her blackened arm. She doubles over, biting her lip and relying on his presence to ground her until the remaining water in her suit takes over.

"Below the belt, Tony," she grits out when she can finally speak without wanting to scream.

"Got you up, didn't it?" The feigned disdain has been replaced by the snarky, jovial tone she's missed so much. She can pretend for a while longer that thinking of this as anything but a hyper-realistic figment of her imagination isn't going to cost her later. "Better angry than ready to die on foreign soil, trust me."

The pain had swallowed her anger whole, but he doesn't need to know that. "Son of a bitch."

He leans back as she straightens, still weak on her feet. "Let's not bring Mom into this."

Isabelle stares at him, drinking in those features she thought she'd never see again until the tightness in her throat reduces to a manageable amount. "Why am I seeing you?"

"We've done this before, you and I," he says. "Bit of a role reversal. I was dying in a barren hellhole and you told me to get off my ass and get home."

She shakes her head, immediately regretting it as her head spins. Something about what he said rings wrong to her, but her brain will melt out of her ears if she tries poking at it further. "So what; you here to return the favor?"

"You're gonna owe me a hell of a lot more, actually. Death's not the worst outcome here." His arms spread like a showman - a perfect reproduction of his real-life counterpart who could never, ever stay still. "What's wrong with this picture, Izzy?"

She stares at him as drolly as she possibly can. What isn't?

He shakes his head. "No. You can make sense of almost everything here." His face twists into urgency, and suddenly she's not looking at her kid brother, but Iron Man. "Maybe I'm a ghost. Maybe I'm a mirage - a result of dehydration mixed with deliberate insomnia, with a pinch of trauma-induced concussion. Maybe I'm a manifestation of the Eternal Eye."

He grabs her shoulders again, forcing her to meet his burning gaze. "But that makes sense. It is a perfectly plausible scenario. As is the fact that you fell through a hole in the universe and landed in an alien world revolving around a black hole. What doesn't?"

She casts one more glance. Ash-smothered clouds blanket the mountains to the west. Ash-choked plains bleakly cover the rest of the surface, lit up by the blue-purplish light of the accretion disk…

Wait, blue-purple?

Isabelle inhales sharply.

Something is reaching out of the black hole.

A perverted ocean of planets and bolide objects in space that distorts around itself; breaking apart and putting itself back together in twisted, paradoxical ways. Unlike the infinite darkness of the black hole, this… mass is lit up like a nightclub, searing colors she's never seen behind her eyelids.

"What the hell is that?"

Her heart skips when she sees the stark dread in her brother's eyes. He opens his mouth, and she knows what he's going to say even before he says it.

"Run."

April 10th, 2024

W.A.N.D. RnD Facility

The Castle

Phil and Daisy are heading towards the labs when someone grabs his elbow. He arches an incredulous eyebrow at Wong, but the sorcerer doesn't retreat. "You don't know the kind of forces you'll be inviting by doing this," the other man urges. "Don't you recall the Battle of New York?"

"Don't you remember the Battle of Earth?" Phil counters. "Hundreds of portals were created there; I saw the footage. Those weren't weakening the fabric of reality?"

"None of those portals were breaches! What you're trying to do is beyond dangerous; you have no guarantee that it'll be Collins that comes through or something else! There are billions of monstrous creatures in billions of realms just waiting on the other side of that veil; intent on devouring our realm! You're opening a door to all of them!"

"Well, I'll be sure to open just a crack, then."

"Coulson," Daisy says uncertainly, but just like Wong, she doesn't back down when he turns his glare on her. "Maybe we should listen to him," she says quietly.

Phil sighs. "If you want to make sure nothing comes through," he tells Wong, " - then, by all means, stay and watch. Bring Reyes for backup, if you like."

"But we're bringing Isabelle Collins home."

Alchemical Laboratory

Daisy and Wong aren't the only ones reluctant. Phil's mood sours further the longer he has to try to get through to the elderly scientist. "You are the world's foremost expert on wormholes, Doctor Selvig. If you can't help us, no one can."

Erik Selvig throws up his hands. He's surrounded by screens and monitors, beeping at odd intervals. There's a variety of instruments lying scattered about that he can't even identify the individual components of, let alone figure out what they do.

"... Einstein-Rosen bridges are wildly unstable," Selvig is saying when Phil finally forces himself to tune in, " - and besides, I don't know how to create them; I've just taken readings when they've occurred!"

"Then take readings," Phil snaps. Selvig rears at his harsh tone. "Compare it to your earlier analysis! At least try to find out where she ended up!"

Selvig blinks at him slowly, and Phil feels as though he's not measuring up to whatever image the scientist has built of him. "You know they told us you were dead?" he says, after a long, tense moment.

Phil shuts his eyes.

"They said that Loki killed you. Stabbed you right in the heart. Jane actually cried."

"Doctor Foster knows," Phil blurts. He can still feel the echo of the resounding slap he'd been greeted with when she and Tony had walked into the Lighthouse during the Decimation. Her anger had waned with that, but Tony's had lingered for the next three years - he hadn't stopped calling him 'Agent' once in that period.

The guilt had never quite left him.

"I know. She was the one who told us after Darcy and I Blipped. She also told me who brought me back, and at what cost." Selvig sighs, pulling the long scarf from his shoulders and draping it over a chair. "I owe Stark a lot; he gave me a job when everyone else thought I was crazy." His smile is sad and old. "Said he liked my crazy."

He sighs.

"I'll do it, Coulson. I'll take my readings, and make you a portal." He locks steely grey eyes with Phil. "On one condition."

"After this is over, I want S.H.I.E.L.D. to forget my number."

TIME: UNKNOWN

LOCATION: UNKNOWN

Isabelle's lungs burn as she leans against the jutting rock. Her skin, her uniform are all coated with a thick layer of ash and dust. "I can't... I can't run anymore. Gimme a second to catch my breath."

Tony hums, hands in his pockets as he stares at the fake black hole vomiting inter-dimensional stomach contents. "You've got ten minutes." The bastard doesn't even sound winded, despite having run for almost as long as and as fast as she had.

Being dead must have its perks, she thinks, and is immediately stricken. "What exactly will happen if I get sucked into it?"

Judging by the look he tosses her way, her tone hadn't been the 'casual-conversational' she'd been going for. "Don't get any ideas. That thing will make you wish for something as awesome as death. Keep running."

"To what end?" The rock doesn't have much in the way of a flat surface, but she manages to park herself on the very edge, giving her abused knees some much-needed relief. "There's no portal, Tony. No rescue. No way out."

He sighs, nods at her suit. "What have you learned?"

She glares at him, then pulls up her hood and activates the suit's HUD scanner. "It's not a planet," she says. "Not the way we think of one, anyway. There's nothing below the surface... just rock, down to its very core."

He nods, brows furrowing. "Just a bloated, oddly spherical asteroid."

"Only source of heat - and light - is from the accretion disk." She exhales. "Tidally locked to the black hole; it's incapable of rotation."

"That'll make it a hell of a lot easier for them to lock onto you from Earth," he points out, as though the reasoning isn't as desperate and absurd as it sounds. He must've caught the look in her eyes, because he scowls. "What, do you really think Phil Coulson's the kind of man to go 'too bad' and just abandon you?"

Isabelle remembers snippets of being possessed. The echoes of the Entity's emotions - of the poisonous hatred that had coursed within their shared body when Coulson had vowed to hunt it down. "I... no," she murmurs. He had threatened to blow her brains out rather than risk her suffering a second longer underneath that thing's control. "He wouldn't let go."

"You can't blame yourself, you know." Yet again, he's able to extrapolate her thought process. She doesn't believe it's wholly an aspect of his hallucinatory nature; he'd been unusually tuned to her mind in life, and she to his. Secrets she may have hidden from him, but he'd always known that she was doing so; it's what had soured their relationship for so long. "It isn't on you."

There's an edge to her laughter that she doesn't care for. "How do I have guilt to spare for Pandora Peters?" Her fingers remember plunging the ice spear into the sorcerer's heart. "I thought I used it all on you."

"The Decimation taught me it doesn't work that way." His gaze turns alert, probing. "But guilt isn't the predominant emotion, isn't it?"

Isabelle pushes herself up. She should've known this was what he was leading up to, all along. "We should leave - that thing is catching up to us."

"Izzy."

Cords twang in her neck as she snaps her head around. "What do you want me to say? No, Tony, guilt doesn't even come close!"

"Then what do you feel?"

Her nostrils flare. "Owned," she spits, wondering if some supernatural force had yanked the words out of her. "Like I was... branded, by whatever took me."

She breathes, attempting to rein in her emotions before her fool mouth betrays her any further. "We're done. Let's go."

She walks away without waiting, and just when she thinks she's lost him, he falls into step beside her as though he'd never left.

April 13th, 2024

Alchemical Laboratory

"What do you have, Doctor?" Phil asks as he walks into the labs. His relationship with Selvig is colder than it's ever been, and he regrets that it has come to this. But he's managed to muffle the initial panic into a tiny ball, which pulses in his chest whenever he stops to think; he's starting to understand why Izzy keeps going even when suffering from burnout.

But today, his agents had reported that the scientist had been quite literally skipping across the labs.

"Look!" Selvig cries excitedly, shoving a cracked StarkPad towards him.

Phil looks, doesn't find anything except for a glitchy screen displaying a line graph with increasingly huge spikes over time. "What am I seeing?"

"The energy levels," the scientist says, jabbing at the screen with thick fingers. "My sensors couldn't handle the surge; they all shorted out! None of my equipment survived! Isn't that brilliant?"

Phil has been forced to learn to fill in the gaps when it comes to following the thought processes of genius-level scientists, so he knows which part of that incomprehensible sentence to zero in on. "Surge?"

"The one that ensued when I switched the gravimetric spikes on!" Selvig's eyes are sparkling, and he's bouncing from foot to foot as he flicks on random switches on his machines. "I installed them around the site of the breach and when I switched them on - bang! Sparks everywhere!"

Phil looks towards Daisy and Wong, who shrug almost in unison, looking just as lost.

Selvig's face seems to fall a little when he realizes that none of them are appreciating his brilliance. He makes an impatient noise, then stalks forward and jabs at the screen again. "My sensors showed a drastic and very specific spike in gravitational and radiation levels… which correspond to only one energy in the entire known universe. An influx of dark energy."

Out of the corner of Phil's eye, he spots Wong stiffening. But Selvig is still talking, so he makes a mental note to interrogate the sorcerer later. "What does this have to do with bringing Collins home?"

Selvig takes a deep breath. "So I compared whatever readings I did get before everything shorted out with all the other data I've collected over the years. I searched everywhere - got nada, zip, zilch. But then…"

A grin brightens his weathered face again. "Then, I called Jane."

"What did she have to say?"

"She's been doing her own research. Abnormal readings from all over the globe. Weird energy levels corresponding to gravitation, seismic, gamma… and then we combined our data, we figured out that they were all the same! All indications of dark energy! Massive amounts, bleeding into our world."

"Dimension," Wong corrects from his corner. Phil turns to look at him; the other man's eyes are squeezed shut. "Dark energy bleeding into our dimension from more breaches." He rubs his forehead. "The few sorcerers I am still in contact with have reported something similar. None of these breaches last more than a few seconds, but their effects linger a long time before dissipating."

"Why didn't you say anything?"

"I didn't think it had any bearing on Collins' disappearance. It's been happening all over the world, and each breach leads to a different dimension. There are millions of them; there's no way to narrow it down."

"You aren't listening!" Selvig cries, banging the StarkPad on a table. "Dark energy is one thing, but this…," he jabs at the screen, this time hard enough that yet another crack appears, " - this spike is gravitational. I'm talking really, really off the charts. The kind of off-the-charts that you get in the presence of something really massive; something that sucks in every. Single. Thing. In its path!"

He straightens. "Something… like a black hole."

Phil's stomach plummets. His heartbeat is heavy, sluggish, and he almost thinks he's having a heart attack, but ever since T.A.H.I.T.I., the old ticker has been perfect. The treatment had cleared out his cholesterol levels too.

So why is his chest so heavy?

"Are you saying," Daisy whispers, her face bloodless, " - that Isabelle Collins fell into a black hole?"

That's why.

To their utter surprise, Selvig rolls his eyes and tsks at them. "If she'd fallen into a black hole, you would've too! In that split second that the breach was open, it'd have sucked in everything within a hundred-mile radius! The Castle would've been nothing but a crater. Besides, weren't you the one who saw a world of sand and rock?"

The sense of relief that hits him makes him stumble. Phil clutches onto the top of a chair and just breathes for a few seconds. "Then what…?" he croaks.

For the first time, Selvig has a sympathetic expression on his face. "She might not be in a black hole, but she's very near it. Almost dangerously close. Barely beyond the event horizon."

"So I told this to Jane, which is when she realized where she's seen such readings before. She compared it, and immediately recognized it for what it was." He swallows. "A black hole, swallowing a world overflowing with dark energy."

Phil finally knows where this is going. He's seen the reports of the Convergence, after all. "The Dark World."

Selvig nods. "The stories I grew up with as a child called it Svartálfheim, the land of the dark elves." He sighs. "The stories left out a lot."

"What do we know about it?"

The scientist shrugs. "I only know what Thor told me. Dead world, birthplace of the Svartálfar, who claim that it's the oldest planet, existed before the universe itself, somehow. Jane described it as a planet of nothing but remnants, ruins of a dark civilization. The accretion disk remains the only source of illumination for the Dark World."

Phil sighs as some of the weight leaves his shoulders. "We need to…"

"No," Wong interrupts. His voice is firm, and he takes a few steps forward, moving deliberately into Phil's personal space. "No. This… this is worse than I imagined. And I imagined bad."

"I told you…"

"That was before we were talking about the Dark World," Wong says, slashing a flat palm through the air. "There's a reason it's called that; there's a reason very few sorcerers draw energy from that dimension. It is not a black hole," he says, his head snapping towards Selvig.

"It's a dark-energy star. Easy to confuse the two; they have similar features - insurmountable gravitational fields, time dilation - but it converts infalling matter into dark energy, which is corroding that entire dimension."

Selvig's brow clears, and he nods distractedly, and immediately turns to his computers and starts typing something furiously.

"Do you remember my warnings to Pandora about the magic she was using?" Wong demands, turning back to Phil. "Imagine more spells wielding such energy… dark energy. Imagine trillions dead, their life force being funneled into an entity that is unimaginably powerful, an entity that is hungry for everything, for the entire universe!"

Phil meets his gaze steadily. "All the more reason to bring her back if that's what she's facing."

Wong is breathing heavily, his usual composure having long disappeared. "I won't stop you, Coulson, even though I want to. But I won't help you either."

And he turns and walks out the door.

Phil stares after him for a long moment. "Doctor Selvig, I hope you have a way to open a breach, because we just lost our best asset."

Selvig snorts. "Magic," he derides. "Just technology we don't understand yet. Arthur C. Clarke. Jane convinced me of that."

"So? Do you have something?"

"You're very lucky she fell into the Dark World," Selvig says, waving his hands. "My data from the Convergence, as well as all the readings that Jane took while she was on that planet should let me," and here he hesitates, " - theoretically replicate the effects of the Convergence in a very, very small, localized area. I'd have to subtract the readings from the other realms that the Convergence opened - that might take some time…" He trails off into unintelligent muttering.

Phil waits. His patience has returned, now that he knows where Collins is. It's still the most dangerous mission he's ever undertaken, but it's worth it. He won't lose anyone else. "What do you need?"

The elderly scientist hums. "More assistants, some gravimetric spikes, Jane's Phase Meter would be amazing, and, oh…"

"I'm gonna need the Castle cleared."

April 18th, 2024

Upper Bailey

The Castle

"Why here, though?" Daisy asks, shielding her face against the wind. Beyond the curtain walls, the river is sparkling blue; like the Hudson, five years of minimal human intervention had repaired what decades of water treatments could not. "Wouldn't it be less dangerous to do it somewhere uninhabited?"

Coulson shrugs. "Something to do with keeping as many factors identical as during the breach. We compromised on the bailey," he gestures to the wide, open courtyard laid out before them. "He wanted to wait for the next thunderstorm, but obviously, we can't wait that long."

"We can't?" Daisy mutters, but her voice isn't as quiet as she'd hoped. Coulson sends her a sharp look. "I'm just saying - you heard what Wong said. If something goes wrong…"

"Nothing will go wrong," he insists, eyes bright and determined. "We'll open the breach, she'll come through, we'll close it before there's any damage. Besides, it's not as if there's going to be a big hole like in the Battle of New York. It'll just be a little thing."

"Little enough for a person to walk through," she mutters, but only when Coulson is well out of earshot.

Coulson's orders had been enough to get the Castle cleared. Daisy remembers a time when such respect for his authority would've been impossible. And after the HYDRA Uprising and the LMD fiasco, S.H.I.E.L.D. had been all but dead in the water.

The Decimation had changed all that. Coulson had been the one to yank the world from the brink of chaos, and now he's up there among the likes of Iron Man and Black Widow in terms of fame and respect. Every man, woman and child knows his name, knows his face. And they trust him.

Trust is the one thing that he's been running after since she met him, or so she'd thought. But now… now he's so very different, because those five years had changed him irreparably. He's… desperate now.

As clearly evident by the fact that he's willing to risk his entire dimension just to bring home one woman.

Daisy doesn't think Isabelle Collins is worth it. But then, it's not up to her to decide.

She's just here to do damage control.

It's nightfall by the time the S.H.I.E.L.D. agents finish installing the gravimetric spikes. They're just running through the final checkups now.

"The radius has to be much smaller than the last time," Fitz explains to Daisy, who's nodding along. "We want to open the breach just a smidge. Any more, and we won't be able to control it. It'll be a squeeze for Collins."

"We should send flares through or something," Daisy says. "So she knows where to go."

"Already got that covered. At the moment of the breach's creation, there will be a massive release of energy. We're gonna be able to redirect it to Svartálfheim for maybe ten minutes before the backlash starts affecting our world."

Daisy shares a loaded look with Coulson. "The explosion will be our flare." His determined expression tells her that he's going to go through with it anyway, but there's a fear there too.

There's a sour taste in her mouth when she realizes that it's not because he's afraid of whatever damage this might cause Earth. No, the fear is very much because Coulson is imagining the possibility of Collins being in the vicinity when the breach first opens up on the Dark World.

"We're ready!" Selvig cries, waving his hands. Everyone retreats from the area of effect, forming a circle around where the breach is supposed to manifest.

"Don't cross the boundary," Fitz warns as they take their positions. "Whatever happens."

"Not planning on it," she assures him.

"You might experience some discomfort," Simmons says, coming up to her right, and handing her her Quake gauntlets. "All the data indicate we might experience seismic activity of some kind."

"This just keeps getting better and better," Daisy says, flexing her fingers inside the gauntlet and mentally steeling herself to absorb as many earthquakes as it took to bring Aquamarine home.

The woman better be falling over herself in gratitude.

"Alright, better hold on to your tighty-whities - ," Selvig shouts over the wind, " - 'cause this is gonna get wild!"

And he slams his hand on the StarkPad.

TIME: UNKNOWN

Svartálfheim

At this point, a brisk jog is all Isabelle can manage; Tony's 'motivating' cheers and jeers notwithstanding. But his constant jabber is more of a comfort than she wishes to admit; her mind has come up with a very realistic simulation. She lets his voice wash over her as she examines her surroundings with a critical eye.

The surface is a deserted wasteland. There are signs of a massive, possibly world-ending battle. But she can't quite shake the idea that this isn't a dead world.

This is a world that never had any life to begin with.

Which makes this next bit baffling.

Because Tony's been steadily guiding her towards ruins, gigantic wrecks of alien starships. "I don't get it," she mutters. "It's not as if the thing's gonna find it harder to catch up to me in there."

"Would you rather be out in the open?"

She doesn't deign with an answer. They make their slow, plodding way to the wrecks, and Isabelle lowers herself to a broad, flat block of metal but misses and hits the ground with a groan. He smirks as he takes a seat beside her gracefully.

Isabelle stares, her heart hot and heavy in her throat. "If I lean on you, am I gonna tip over?"

The smirk disappears. "Find out."

She does so unwaveringly, sighing when she feels a line of solid warmth pressed against her side. Tears trickle down her cheeks. "You don't need to wait around," she whispers. "I'll be there soon enough."

"You're not dying," he says impatiently.

For a moment, she allows herself to believe him. "Then why...?"

Silence falls, for so long and so deep it's only the physicality of him that keeps her from panicking. "Because I need you to choose them."

"What?"

He sighs. "I know what you've been doing. But there's no peace at this end, Izzy. What I said wasn't a lie - you have been abandoning them. Pepper, Rhodey, Peter, Morgan - they need you."

"They need you more."

"Not now. I've done my part." He shifts, making himself comfortable. "I get wanting to be selfish. Five years - I chose them. Didn't try as hard as I should've to bring you back."

And all of a sudden, she's angry. She shoves at him hard. "You sure as hell found the time to build a coffin instead of a suit," she snarls. "Or did you think no one would go over the specs of Mark 85?"

His gaze is infuriatingly calm. "I was a futurist, Izzy. I always saw the bigger picture, which sometimes meant not seeing myself in it."

"You didn't even try."

"Neither are you."

She recoils. But his words, cruel though they might be, hold the clear note of truth. She'd barely stayed for the funeral, let alone past it. "You can't possibly expect me to be grateful."

He shakes his head. "I expect you to not waste it. I'm gone, and like it or not, I'm not coming back."

His eyes flick to somewhere past her. Without warning, he grabs at her shoulders, clutching tightly. "Save the ones you still have left."

His expression in that moment would be branded in her memory forever.

Because that's when the world lights up.

April 18th, 2024

Upper Bailey

"I'm telling you, the breach is open!" Selvig cries, the device clutched in his flailing hands almost catching Phil in the chin. "Every scan I've taken confirms that!"

The humming, vibrating circle of gravimetric spikes surrounding an area of empty space contradicts the scientist's words. No portal had appeared when Selvig had switched on the contraption; no sparks, no rip in the universe, no earthquakes, nothing.

"Is it invisible, then?" Coulson asks, his temper fraying. "Should I throw something in, just to make sure?"

Selvig opens his mouth, then shuts it just as quickly, his eyes lighting up. "You know, that's not a half-bad idea," he says, then looks speculatively at the machine, which Phil remembers belatedly is the Phase Meter they'd borrowed from Doctor Foster.

"Sorry, Jane… I'll make you another one." And before Phil can even think about stopping him, he stalks forward, right to the edge of the circle, and tosses it in.

Three things happen in that instant.

"No, wait, don't!" Fitz cries out, making a sharp motion towards Selvig, only to be yanked back by Simmons.

Daisy draws in a quick, shocked breath beside him, her hands spreading wide, her gauntlets trembling.

And with a horrific shearing sound, the Phase Meter rips apart, its shorn pieces hurtling away from the center as the air itself shudders from the impact, a second before the backlash hits.

The pulse is little more than strong wind buffeting them backward, but Daisy's muffled cry lets him know that if not for her, it would've been a whole lot worse. She sways, and when he moves to assist her, she shoves him aside and stumbles towards a huge hole in the curtain wall. Huge waves ripple across the river as she releases all the vibrations stored in her gauntlets.

Phil looks around. Selvig had gotten the worst of the backlash, having been thrown to the ground. The scientist hasn't attempted to pull himself up, doesn't even seem to register Fitz shaking him, just stares blankly at the contraption in front of him.

He finally turns to look at the circle itself. Even without a background in science, he knows that it's utterly ruined. Most of the spikes are out of formation, or just snapped in half, and the ground is charred and smoking.

There's no sign of portal, or of anyone else.

Phil's stomach drops as the truth he hadn't allowed himself to admit hits him.

She's gone.

TIME: UNKNOWN

Svartálfheim

The explosion lifts her off her feet and throws into the side of a bulkhead. Her back arches around a half-melted beam, and something sharp scrapes the underside of her jaw, almost decapitating her.

She tumbles to the ground, and rolls for a few seconds before coming to a stop. The pain is fierce, arcing across her back and head, and there are starbursts behind her wet eyelids, which refuse to open against the onslaught of light and heat surrounding her.

The ash is hot beneath her torn, blackened hands, and the smell of burning metal and flesh makes her retch. But despite all this, despite the cloud of confusion crowding her mind, one thought manages to struggle its way free.

In a world of darkness and death, light can only mean one thing.

Hope.

Tony's upright, edges fading into the inferno his bright, brilliant eyes reflect. His mouth, like the Cheshire Cat, is the last thing to disappear, " - tell her I love her 3000."

She pushes herself to her feet. Blinking to let her eyes adjust, she absorbs the very last drops of water in her suit and steps directly into the roaring conflagration.

It still burns, but it's not as bad as it could've been, she thinks to herself, as her skin splits and blisters. She squeezes her eyes shut, lets her instincts carry her over to the hottest part of the fire-engulfed wreck.

She knows she's reached it when, over the roaring of the flames and the distant, unearthly shrieks, the air in front of her makes a sound like cloth ripping.

Without opening her eyes, trusting in her gut, and whatever it is that's waiting for her on the other side, she throws herself into the breach.

MCU Context:

Decimation: So, when I first wrote this chapter, I didn't realize that Jane Foster hadn't survived the Decimation in MCU canon and Darcy Lewis had (as far as I know).

Now I can't change it because Foster's role in my canon will be very important in the coming decades.

So I'm kinda handwaving this by doing it this way - somehow, due to the butterfly effect caused by the existence of Isabelle Collins in this universe, Jane Foster was not chosen randomly by the Gauntlet when Thanos Snapped his fingers - instead, Darcy was. Jane was one of the Survivors who worked with Tony Stark and Phil Coulson in an attempt to bring back the Decimated.

Selvig was Snapped too.

General Context:

Dark Energy and Dark Matter: This is actually a real, actual concept.

Most of the universe is made of dark energy. It's not actually dark, it's just called that because scientists are 'in the dark' about it.

This term is hugely important in my fic. My entire plot hinges on dark energy. You will notice that I use this term very, very carefully - I don't go throwing it around willy-nilly.

Dark Energy is responsible for expanding the universe, pushing away all stars and all planets and all matter from each other.

Dark Matter is the thing that holds our galaxies together. It produces gravity because scientists have determined that the percentage of ordinary matter in our universe doesn't produce enough gravitational force to hold it all together, so it must be 'dark matter'.

The two terms are not interchangeable terms - in fact, they're basically opposites.