She's alive.

Alive, but lying motionless on a table with that…. thingon top of her chest, practically crushing her with the sheer weight of it. She's far from okay, but she's alive. Maggie struggles to hold onto that thought as she reaches for Alex's hand, listening to Kara and J'onn arguing outside.

Alex is breathing – she can see the steady rise and fall of her body as it fights against the parasite – but Maggie just can't. There's a list of priorities being written somewhere in the back of her mind, and breathing? Breathing isn't even on it right now.

Don't look at her, she tells herself, but does it anyway. Acid burns in the back of her throat, ready and waiting to choke her the moment she loses her grip, and Maggie thinks that maybe she already has, because Alex's skin is so pale it's virtually translucent, and cold. It seems like the parasite is draining the life from Alex's body exponentially, dragging the fierce vitality that's so simply Alexout from under her.

Maggie has managed to convince herself lately that she'd been able to let go of the trauma from the sight of Alex floating in that tank, from the burning feeling in her own chest at the knowledge that they'd been mere seconds away from being too late to save her, but even so, the unnatural coldness of Alex's hand in hers brings back the crushing, paralysing dread with a vengeance, and it mirrors the creature wrapped around Alex's body right in front of her.

The sound of the door opening makes Maggie jump, and she tears her eyes away from Alex's face to look up at Kara and Lucy. J'onn follows behind them, wearing a serious expression that matches Lucy's own steely determination. Kara is hiding her panic behind her stoic Supergirl expression, the perfect display of justice and superiority in the face of a monster. Maggie wishes she had something to hide behind, a cape to fling around her shoulders and a symbol on her chest to justify it all.

Lucy's hand is on her shoulder, she realises, but Maggie is frozen, still gripping Alex's hand like it's the only thing tethering her to the Earth. Which, from the way Kara is avoiding looking directly at her, it might be.

"Detective."

It almost hurts that J'onn addresses her so formally, as if even he has discarded her, leaving behind what feels like only bleak professionalism and the attempt to understand why she's clinging to Alex's lifeless body like it's a drowning victim to a raft. Read my mind, she thinks, because privacy isn't something that even crosses her mind, and she loves her, dammit.

Her whole body has been so tense for so long now that every tiny movement feels stiff and awkward, like someone poured cement inside her limbs, but she forces her body into an upright position, remaining in her spot between Lucy and Alex.

"Just," she swallows, gritting her teeth against the nausea twisting in her stomach, "just tell me. Please."

Lucy's grip on her shoulder tightens in a reassuring squeeze, and Maggie thanks her silently for keeping her grounded.

"It's the same species of alien parasite I was attacked by a while ago," Kara tells her, "a Black Mercy."

"It's trapping Alex in her own mind, right?" Maggie asks, "she mentioned it. Before."

Kara grimaces, shifting her weight uncomfortably from one foot to the other.

J'onn clears his throat, "Yes, Maggie. But it's a little more complex than that, unfortunately."

"Complex how?"

"Alex is experiencing a fantasy which she believes to be reality. Her ideal world. Perfection, whatever that is to her, is what she's trapped in."

"H-how do we get her out?"

Lucy glances from the screen monitoring Alex's vitals to Maggie's face. "Removing it by force is not only impossible, but it would kill her."

Maggie catches sight of the twisted piece of metal and padded material in J'onn's hands – something resembling a headset. On impulse, she almost snatches it out of his hands, desperate for a way to get to her, but reconsiders the idea when he starts to explain.

"The only way to save Alex is, well, Alex. She has to consciously reject the fantasy herself. We have the technology for one of you to... attempt to convince her that it isn't real. In basic terms, you enter Alex's mind and engage in the same hallucination she's experiencing."

Maggie stares at him, her eyes wide.

"How do you convince someone that their happiness isn't real?" she whispers faintly, her fingers itching to tear the thing from J'onn's hands and throw herself into whatever's happening in Alex's mind without a second thought.

Kara's jaw clenches into an unforgiving line as she steps forward towards Maggie, her arm outstretched as if to touch her, but she reconsiders the decision, drawing her hand back awkwardly and standing with her hands on her hips like this is just another day on the job. It's not. She's terrified, that much is clear, and Kara is like a child in many ways, but Maggie knows better than anyone, including Alex in all likelihood, just how dangerous that childishness can be, especially when it comes to the woman they both love.

"Maggie, I was in Alex's position once and I only made it because of her. I have to do this for her."

The juvenile fear in Kara's eyes clashes horribly with the 'step aside, ma'am' superiority complex that's bitingly obvious as she towers over Maggie, and the detective feels the anger boiling under her skin. She doesn't hate Kara – even if she'd wanted to, she can't deny that the woman is genuinely good, and loves Alex with an awe-inspiring fierceness that only succeeds in mirroring her own feelings, but deep down Maggie knows that behind the superhero front is a traumatised child who can't understand that some people are just badand sometimes there are no happy endings.

"I love her, Kara. I can't just sit here!" Maggie chokes out, and she means it, God, of course she does, but what she really wants Kara to understand is exactly what she told her before, with bits of smashed laptop dusting her hands and adrenaline still rushing through her veins.

I have just as much to lose as you.

And maybe that's not even true, part of her whispers, because Kara has a hundred people who love her, and she loves them too, and maybe Alex is her world, but there are other planets in her solar system. Maggie is alone. Always has been. It's disgustingly selfish, Maggie thinks, but part of her wants to scream that Kara has everything and Maggie has Alex.

HadAlex.

Instead, what comes out of her mouth is a choked "please" and a desperate glance at J'onn, and none of them are saying anything, and Maggie can't breathe. The walls are closing in, and Lucy is grabbing her hand and holding her like she cares, which Maggie would be confused about if she wasn't so broken.

Kara's eyes dart awkwardly to Maggie's neck, which she'd forgotten about until now, and then to Alex, and guilt rushes through Maggie's body with a force that leaves her breathless. The primal instinct to get outtakes over, and she struggles against Lucy's grip, unsure of what she's even trying to do.

Lucy releases her, and the claustrophobia lessens, but by the time Maggie can breathe again without almost dry-heaving, Kara is already slipping the thing onto her head, an expression of concentration and something that looks too much like relief to make any sense on her face as she lies down, thankfully out of Maggie's sight.

The door slams loudly when Maggie shoves Lucy away, a desperate need to escapedragging her down into a messy spiral of guilt and horror. She shoulders her way through a group of uniformed agents without blinking, and her chest aches with the effort of trying to gulp down enough air when she makes it through a random door, ending up in a bathroom. Her eyes burn with tears as she clutches at the sink, fighting to keep some kind of grip on reality as anguish threatens to swallow her whole.

It's almost ironic, and entirely excruciating, that Alex is in a fake paradise while Maggie is living out her own nightmare, all in the same building. It's then, with that thought and the sight of the painfully obvious bruises on the side of her neck, that she gives in, sobs wracking her chest and ripping through her with a force that rivals the agony of watching Alex through that little screen and wishing more than anything that she was the one on the brink of death instead.

Like Alex said, nothing has changed, and maybe nothing ever will. In Maggie's all-too-experienced opinion, that's indisputably bad.

Someone is knocking on the door.

Maggie splashes cold water on her face, on the back of her neck, and hopes to God that they go away. It's probably Lucy, she reasons, looking out for her because of Alex. To Maggie's shock, the woman who greets her with a weak smile when she opens the door is none other than Eliza Danvers.

"Maggie," she murmurs, holding her arms out, and Maggie sort of hates herself for immediately falling into her almost-mother-in-law's embrace.

"She – I wasn't there, I should've-"

Eliza shushes her, stroking her hair soothingly like she's comforting a child, and Maggie immediately has a mental image of Alex comforting her own child in exactly the same way.

"You did nothing wrong, Maggie. This is not your fault, I need you to understand that."

Maggie lets her kick some random people out of a conference room and push her gently into a seat with a cup of water that has seemingly materialised out of nowhere.

"Did you see the… thing?"

Eliza nods painfully, clasping Maggie's hands in her own.

"You wanted to go instead of Kara," she observes, her eyes soft as she looks down at Maggie with a tenderness that makes Maggie feel like she's standing on her Aunt's doorstep again and praying to the God her parents couldn't make her believe in that she won't be spending the night on the street.

"Yeah."

"She said no?"

Eliza doesn't seem at all surprised, maybe even a little apologetic.

"Not even that. She just went ahead and did it."

Sighing, Eliza glances through the doorway to the room where both her daughters lie unconscious. Maggie freezes, realising that yes, she had said that out loud, and yes, the person she'd said it out loud to is Eliza.

"I'm sorry, I-"

"It's fine, Maggie."

There's a pause as Maggie pulls her hair back to cover the right side of her neck, triggering a sudden burst of feeling as she remembers the gentle tug of Alex's fingers tangling in her hair just hours ago. She wonders briefly if Eliza notices, her hands curling tightly into fists.

"Alex called me right before she went back to the warehouse," Eliza admits, "I begged her not to go but she… you know better than anyone that there's no reasoning with her when she puts her mind to something."

"What did she say?" Maggie's heart starts thudding in her chest, panic bubbling over as Eliza shrugs.

"She was upset. I think she said something about messing something up, and she mentioned you. Clearly, she feels guilty about what happened between you, but I suppose that's between you and her. But it was mostly about Kara."

Maggie's eyebrows lift in surprise.

"Kara?"

"Yes, she's mentioned her concerns in passing a few times, but she never wanted to address it, and then she called me suddenly this morning and started talking about how Kara always ignored you, or distanced herself because she was jealous of sharing Alex with someone else. Alex said it made her cold, reckless, even."

Maggie's jaw hurts with how tightly she's clenching it to attempt to stomach her own failure as Eliza looks at her.

"I never meant to take Alex away from Kara, I really tried to show her that, but we never really, I don't know, Kara is so close to everyone else, but I always got the impression that she just… tolerated me."

"You're not upset about that?"

"Alex and Kara are two sides of the same coin. Maybe there's no room for someone else."

"Maggie there has always been room in our family for you. There still is. Alex is Kara's world, her only true connection to humanity, and when you came along, she felt that her bond with her sister was threatened, which of course it wasn't. I know how hard you worked to make those two talk to each other about the important things, so thank you."

Eliza's words are kind enough, and Maggie understands that she might even mean them right now, but the feeling of security and safety is just that – a feeling. She's had it before, with her parents, more exes than Maggie cares to remember, and with the Danvers, and each time, the promise of forever had felt real, until the ground disappeared again from under her feet and she was left to fall alone, over and over.

And here she is, letting herself believe it all over again.

"You don't have to say that just because Alex and I…"

Alex and I what? she asks herself. Maggie doesn't know the answer.

"I love you like a daughter Maggie, that didn't change because you and Alex thought you couldn't make it work."

"You think we could? If… if Kara gets her out of there?"

"I think that you both love each other, and that doesn't just go away because you want different things. Look, Maggie, when Jeremiah and I first started dating, I made it clear right from the beginning that I wasn't interested in having children."

"But-"

"I'm not trying to encourage you to change your mind, quite the opposite, really, but the thing is, life can change completely in a second, and there's no way of anticipating the disasters that it throws at you, or the moments that you'll treasure forever. No one knows what's going to happen tomorrow, especially with the lives you all lead."

"You think we could try?"

"Alex has already decided that even if she wanted to, she can't be a mother. Not right now, anyway. Maggie, what I'm trying to say is that when you have something this strong and this powerful, don't let it go for a future neither of you can predict."

Maggie nods slowly as Eliza leans back in the chair.

"They'd tell us, right? If there's any change?"

"Of course."

Eliza eyes her doubtfully as her eyes fix on the closed door of Alex's room.

"Come on," Eliza murmurs, gesturing for Maggie to stand and leading her back to Alex as if reading her mind.

/

"How long has it been?" Maggie folds her arms across her chest, feeling nervous alone with J'onn now that Lucy had dragged Eliza outside to find a DEO file that could have more information on where Cadmus got the Black Mercy.

J'onn stands awkwardly by the wall, watching over the Danvers sisters anxiously.

"Two hours."

"How long can they stay like this for?"

"Not much longer," he admits, his frown deepening as he focuses on Alex's face.

"Can you tell what's happening?"

J'onn shrugs, "hallucinations are a little different to ordinary brain activity, so to a certain extent, I can't read their minds, but every so often I hear some of what Kara is thinking."

Maggie falls silent, unsure of whether she wants to know what exactly that is.

"In theory, the more I'm able to hear from Alex, the closer she is to rejecting the fantasy, the closer she is to accepting reality," J'onn murmurs, looking pained.

"Can you hear her?" Maggie whispers, dread twisting her stomach into knots.

J'onn shakes his head once, and if Maggie had blinked then, she would have missed it. Somewhere in the following seconds, Maggie's throat closes up and the silence is broken suddenly by the sound of the door sliding open. Eliza asks for J'onn, murmuring something about Lex Luthor's research and J'onn's psychic powers. J'onn gives Maggie a look that's clearly meant to be reassuring, but feels a lot more like she's back at school, back being the introverted kid who always sits at the back of the class and occasionally got sympathetic looks from teachers.

Lucy appears a few minutes later, allegedly to check on the Danvers sisters' vitals, but seemingly more to bring Maggie coffee and a donut that if Kara were conscious right now, would no longer exist.

Maggie mumbles a "thank you", burning her tongue almost immediately on the scalding liquid and her desperation to stay alert. Lucy leans against a counter across from her, watching silently.

"You should eat that," she gestures to the donut Maggie hasn't touched.

Maggie shrugs, "I'm not hungry."

"You're just like Alex," she mutters, almost to herself, but when she looks back at Maggie there's a spark of something resembling amusement in her eyes.

"Is that a good thing?"

"Probably not," Lucy admits, offering her a weak smile, "can I ask you something?"

"Shoot."

"Did Alex ever tell you that she called me the minute you left that crime scene?"

Maggie's eyes widen in surprise, and she tilts her head to the side, searching for something she doesn't find in Lucy's face.

"No, she didn't."

"Well, she did. She kicked you off your own crime scene – never tell her I said that – and immediately called me to tell me about this annoying detective interfering with DEO business."

"Annoying?" Maggie smiles at the memory, hoping desperately that there will be a future for her to argue with Alex over jurisdiction.

"Yep. She called you annoying and ridiculously smart," Lucy smirks, "her words. Then the next time you bumped into each other I got another earful, but that time she mentioned your dimples and how she really wanted to be friends with you, but she didn't know why, because you messed up her crime scene."

Maggie hadn't realised that there were tears in her eyes until now, and she rubs them away quickly before Lucy can see.

"She was so deep in the closet I'm surprised you called her out on it, honestly."

"In my defence, I thought she was out the first time I met her, but then when she accidentally asked me out I realised what a baby gay she was."

"Good times."

"Yeah."

"You know, she stopped calling around November, and Kara stopped complaining about walking in on you about the same time."

"She ghosted you because we broke up?"

Lucy snorts, "pretty much, except she drunk dialled me once a few months ago, full on Alex Danvers level wasted," her voice lowers and she looks over at Alex, "and…I realised that she was broken."

Maggie's head snaps towards Lucy, her breath catching in her throat.

"I-" Whatever Maggie had been about to say is interrupted by a sudden incessant beeping.

Her stomach drops as people rush into the room, her eyes immediately drawn to Alex, and the perfect stillness of her body. But it's not Alex, it's Kara. J'onn barks out an order to "pull her out, now", and the flurry of movement ceases as Kara's eyes fly open.

She sits up hurriedly, her chest heaving. Maggie freezes as Kara's eyes immediately lock on her.

"Maggie, I can't – Alex needs you. It-it's you."

Maggie takes the device out of Kara's hands, nodding at her in thanks.

"J'onn?"

"Do it."

Lucy is the only one who looks at her instead of Alex as Maggie takes Kara's place on the little bed, her chest tightening as she slips the device over her head.

"I've got you, Sawyer," she promises, hooking the monitor up to her arm.

It's almost like falling asleep. Her eyes fall shut by themselves, and then there's nothing.

/

The world falls into focus, and Maggie quickly realises that she's standing in the hallway outside Alex's apartment. It's familiar, something she can work with. You're undercover, Maggie thinks over and over, trying to convince herself that it's just another mission, but it's not, and her heart is thudding at a hundred miles an hour as she pushes the door open.

Alex turns around, a bright smile on her face.

"Hey, babe. You're home early."

She steps forward to kiss her cheek softly, and Maggie can feel the smile against her skin. Her heart is in her throat, because she's suddenly aware of the ring on her finger, and it's a wedding ring, and Alex is wearing a matching one.

Alex releases her, turning back to the kitchen for a second. It's then that Maggie notices that, one, Alex's bedroom has a door, and two, there's another door next to it. Her eyes fall on a scribbled drawing taped to the fridge, the childish handwriting indicating that one of the blobs is called "Mama".

Maggie's body goes numb with shock when a little girl appears in the doorway of one of the bedrooms. She's probably around five, Maggie guesses, and with dark hair almost like her own, and bright green eyes shining as she beams up at her.

"Mama!" she exclaims, "You're home!"