Ooookey that summary is... accurate but... well decide for yourself.
Some of the dialog borrowed from Person of Interest s5, it inspired me to write this so...
OH! INFORMATIONS FOR THE STORY
It's weeks after 3x13, Lena and Alex were together trying to figure out what's happening to Sam.
Sam and Alex started dating some time ago (few weeks)
And that's all I can remember right now.
Alex wakes up with a headache, last thing she remembers is fist connecting with side of her head. Opening her eyes slowly she is surprised to notice she is surrounded by darkness. Alex raises hand to her forehead but doesn't feel anything sticky, it allows her to sigh in relief, of course there might be some damage, but it's not an open wound at least. She rolls on her side, then stomach and, using hands, gets up from the ground, groaning. Movement doesn't help with her headache.
Now that her eyes adjusted to almost total darkness, there are, five meters above her, dirty windows, those on her right let through more or less, usually less, moonlight. But it's enough for Alex to know she is in some abandoned warehouse, big warehouse. She turns around but there are no visible tools that could help her escape this place.
With a sigh she starts walking in no particular direction, knowing that soon or later she will reach a wall and find door, with a lot of luck it will be open, knowing her luck it is going to be closed and secured by seven locks.
With a head filled with such thoughts she makes dozen steps before there is loud crash. Alex turns around to see hole in the ceiling and rumble under it.
The hole is actually useful as it allows more light to slip into the warehouse, illuminating person standing in the middle of that mess.
She is in black costume, with that cursed emblem on her chest, cape billowing behind her, dark lipstick on her lips and that damn, now completely unnecessary mask on her face.
Alex takes a shaky breath - "Sam..."
In seconds she stands in front of Alex, grabbing her throat and tightening hold on it, slowly. Her eyes blink red, just like back at Sam's apartment, some time ago, when Alex told her what she and Lena think is causing her blackouts, they worked on this togheter for weeks. In perspective, she is glad she did not mention Lena in that conversation or else she'd be here with Alex, instead taking care of Ruby.
As soon as those eyes are back to their normal brown color, she speaks for the first time, with that modified voice Alex hates so much, especially now - "There is only Reign. Your Sam is dead. I killed her just like hundreds of others." - Sam... Reign squeezes her throat a little bit harder and Alex knows, if she survives this, it's going to bruise, just like her head - "And now, I'm going to kill you too."
Alex somewhat knows that the kind of speech she used on Julia won't work here, she feels daring and so she takes a risk - "So why haven't you?" - she is able to utter through her squeezed throat and Reign eyebrows raise slightly at that - "Because you had many chances, even in last... since our chat back at home. You could've killed me there, instead bringing me here. You could've killed me when I was unconscious, the second I woke up, you could kill me now, using a little bit more of your strength and crush my throat." - she is forced to make a pause as Reign is lifting her up in air - "But you didn't and you won't." - speaking is harder now - "You want to know why?" - Reign says nothing, doesn't move and Alex takes it as a good sign, Rao, if Kara will ever find out that this is what she said to Kryptonian, Worldkiller! No, that can't happen or else she'd go bankrupt in a week trying to appease her sister with food - "Because somewhere in your heart, you know we belong togheter. Me and Sam."
"You are delusional, human. There is no Samantha Arias." - Reign's hand is bailed into fist - "She does not exist anymore." - it, in Alex opinion, sounds like Reign is trying to convince herself, but she has no time to think about it as that fist connects with her stomach and sends her flying several meters, before falling and bouncing off the ground to finally slow down and tear skin on her back in the process.
Standing up she winces when material of her shirt rubs on her full of wounds back. - "It's okay Sam, we will work through this." - she says just before hand grabs front of her shirt and pushes her against the wall, it causes her to hiss in pain. When she opens her eyes, she is met by pair of red ones, then notices a fist raised up, ready to strike. Alex quickly looks back into the still red eyes of her girlfriend, swallowing she realizes that it indeed may be end of her and curses in thoughts, if she dies Kara is going to find a way to bring her back just to kill her again for not waiting, as she asked Alex to do. - 'I'm sorry Kara' - she thinks.
Reign smirks - "You are no longer so confident human, I wonder why?"
Alex exhales - "Sam..." - the fist connects with a concrete next to Alex's head. She looks at Reigns face again, she's blinking but her eyes are brown - "Sam?" - Alex asks tentatively and those eyes lock on hers.
"Alex?" - Sam looks at her, unseeing, then she focuses and lets go of Alex's shirt - "Wh- what... is happening?" - with a thud Alex falls to the ground - "Where are we?" - then Sam looks at herself while Alex is standing up - "And what am I wearing?" - next she looks back at Alex, her voice wavering - "Alex?"
"We are... that's actually good question. We are going to figure that soon." - she slowly steps closer and wraps her hands around Sam, hugging her, while she reasts her head against Alex's shoulder, hugging her back, unknowingly making Alex's wound hurt more - "As for the other questions, I'll answer all of them, but first I need to get you to safety." - says Alex as she kisses top oh her girlfriend's head.
"Ruby..." - it's a yawn rather than a question, but nevertheless Alex understands.
"She is safe, Lena is taking care of her." - she reassures Sam - "We need to go."
"Mmm... tired..." - says Sam while snuggling closer to Alex who smiles at that action.
"It's okay, sleep. I'll keep you safe." - with that words she takes Sam in her arms, carrying her bridal style, that's also when she notices the door to her left, it makes her sigh with relief, looking for a door with Sam in her arms and wounded back would be hard.
Alex walks to it and somehow manages to reach the handle without waking or dropping Sam, she presses it and door open, what really surprises Alex, with quiet creak. She looks at Sam but she is still sleeping, then walks out the warehouse.
Alex looks around quickly, not seeing any other buildings, just sand. She sighs and says quietly - "Supergirl." - Kara will be able to hear her anyway and she won't wake Sam.
Not even a minute later red-blue blur lands not far from her - "Alex! There you are! I have been so worried! You are hurt?" - asks Kara while examining her back, face and what she can see of her neck - "I told you to wait for me dummy!" - the last sentence is said reproachfully.
"I know, I know, I just couldn't wait anymore." - Kara huffs at that - "I'm sorry."
Kara points accusative finger on her - "You're lucky I love you."
It makes Alex smile - "I know, I love you too, but can we go now?"
"Of course!" - it is said with a smile, full-blown, teeth showing smile - "Where to?"
Alex furrows her brows holding Sam tighter against her - "The DEO"
Hope you enjoyed! Thanks for reading. Sorry for any possible mistakes.
There might be a second chapter. No promises tho, that's why it's marked as complete.