So Clark calls on Kara to investigate something with him. I hope you like this!

Disclaimer: I do not own Supergirl.

Clark has taken several days off from work to be in National City, spending some time with Kara but when she is at work or spending time with her sister he is investigating something. On one of his last quests he came across documents that belonged to Lex Luthor, and one of them trailed to National City, in the ocean. He has been keeping tabs and trying to find a mysterious sphere that he found a diagram for, finding it odd that there had been no reports of it he had to scope it out for himself.

Finally he caved in and asked Winn to look into it for him and within no time the tech guy had called him up to say he found something. When Clark found out the coordinates he called his cousin who is arriving now at his location, hovering over the ocean with just a tad of land over 30 feet away.

"So Kal, what are we up to?" Kara asks settling next to him.

"You know my history with Lex… well," he looks down at the water before him. "Last week when I was finished with getting a scientist arrested in his labs I found a secret passageway," he smirks and looks at her, "I know, original right? Anyway, I was going through some of the paper work to see if any of it had to do with the test tubes in the lab in the original room when I came across notes from Lex. Now I haven't seen his work in months, the last I heard about his work was when you had to deal with Lillian," he looks at her on a more serious note. "I came across diagrams and it looks like a machine that was going deep sea diving to get a particular mineral, whatever it is I need to know so the next attack he has planned, if it's involved I'll be prepared."

"And you called me out here because you wanted back-up in case of security measures?" Kara enquires and he nods slightly.

"This is your city, not mine, I asked Winn for help and he was eager to do so," Clark smirks, "that and I enjoy working with you when we get the chance."

Looking into the water Kara spots something coming towards the surface, but not quickly, "is this the mystery machine?" she asks and he nods.

"Yes, it is programmed to come up to this location from what I gathered. Apparently when I was investigating earlier I was triggering it to come up but it takes so long and it isn't programmed to go back down until it reaches the top. Winn found this out from my scouting," Clark watches it come through the surface of the water on propellers.

The hatch opens and they both hover closer to it, Kara motions for him to enter first and he does, once she is inside the door closes and it begins its decent. Button lights coming on as soon as the door closed, screens, lights to see around them, and what looks like joy sticks to maneuver something.

"Did the notes say anything else?" Kara asks as she takes a look at a screen and flips through some logs.

"Other than the fact he's always on the hunt for kryptonite or another way to jab at me for our ruined friendship," he purses his lips at the thought and remembers Kara is friends with Lena. "I hope your friendship with Lena is stronger than what I had with Lex."

Kara looks over her shoulder at him, "so do I… she considers me, well Kara, to be her best friend. I just wish I could tell her who I was but I fear she'll cut me off," she turns back to the screen and keeps flicking through until she finds a video file.

"You think she won't forgive you for not being honest with her from the start?" Clark asks as he finds a clipboard with stats written just like the other notes he'd found.

"I don't know, I just hope she'll understand and forgive me in the end… look at this," Kara says and he walks over as she finds the play button.

Lex Luthor's face shows up as he's leaning into the screen, Kara spots where the camera is and returns to watching.

"Log 47, I found it, and with it I will set up the bread crumbs… I can only hope to set this plan in motion before I get caught. In zone 4, section 12 I found the mineral. And from what I've tested with what I managed to bring down with me, it is working. This mineral is attaching itself to Kryptonite and begins to have its own green vein glow when attached, I need to study it further but it looks like its origins came from space. Perhaps when," his face scrunches up, "Superman's" he seethes the name like its venom. "Cousin came down she had it trailing with her pod."

Clark and Kara make brief eye contact about the mention. "Dr. Intordows will continue with my work but only through my instruction, he seems excited but terrified. He is the only one I trust to continue with my work."

The machine touches down to the bottom, which took several minutes due to the pressurisation. The sphere hits something on the bottom and the screen then fizzes out, triggered by what it hit; the doctor Clark last apprehended appears on the screen.

"As a fail safe, Lex felt you would find his notes on what he was doing down here," Dr. Intordows says in a sing song voice before laughing, "which is why I came and retrieved the last of the sample. Yes you are on the trail so I had to do this before you got too close, the reason you lost track of me was because I came here," he points at the camera. "And I bet you brought your cousin along! Lex said he saw you both in the news in National City, so I set up a trap for presumably the two of you."

They both step away from the screen to look around and see the lights flickering out to all of the consol buttons and switches.

"Yes, tick-tock, power is being let out, tick-tock there's a trap door above you, tick-tock only one will make it out," both of them look up at the door and that's when they see it. The green lining the rim. "You have just a few minutes till you're out of air, but once one leaves… the Kryptonite is set up to seal the other inside. Unless we calculated wrong," the Dr sounds like he is pouting, "then Superman gets out alive… but if we're right," his voice sounding sinister and changes to a deep dark, "one of you walks away."

"Okay, Kara I think I saw cables on the top, I'll squeeze through and pull the sphere to the surface," Clark says and Kara shakes her head.

"No way, my job when I came to Earth was to protect and look out for you; I'm older so I'm going through. We can take turns okay? We're really far down, when I can't handle it anymore I'll come back in and you can take a turn because I'm pretty sure we can't hold our breath for that long," Kara counters while folding her arms across her chest.

"No, I invited you down here, I'm not risking your life for my mistake at being curious," Clark says and Kara looks up at the door.

"I'm smaller, we need a small opening before the Kryptonite closes the door and we can't risk that much water getting in. If you go out then more water comes in on me," Kara raises her eye brows at him, daring him to challenge her further.

He looks really frustrated and knows that time is running out, clenching his fists tightly, "okay! Fine, I'll open it for you, but Kara if you can't do it then you come back in. Got it?"

She takes a moment to think about it, but nods, "open it cuz."

Looking up at the door above them again, he reaches his fingers into the crevice and manages to push them in and separate, "take a deep breath and get ready to go!" Clark says feeling the kryptonite already, he pulls as much as he can and water starts to gush in. He screams as he pulls it open just enough that she jumps through. As soon as she does he lets go and the first seal moves away to reveal the hidden liquid Kryptonite door, wiping his face of the cold water he stares in anticipation.

Kara moved quickly, grabbing what he spotted, the cables and pulls, the ocean water pressure feeling like she is stuck in silicone wrap in cement. Thanks to the Kryptonite the water actually feels cool, she heaves the machine up and aims straight up, at least she hopes it is from this far down.

Clark feels the machine shift and start going up, moving faster than it had before, "come on Kara… if you need a break come in… we're going to make it through this."

Fish swimming around her and the sunlight dances on the surface in the distance, too far, she clenches her teeth as she starts to feel the last bit of air she kept in her cheeks escaping.

Looking around as best as he can, without any lights he sloshes in the shin deep water peering through the windows and finally sees how far they are. He can just barely make out Kara and sees the bubbles. "Come in for a breath Kara!"

But she doesn't, she pushes, using as much of her energy that she can to pull the machine through the water, the pressure is already much lighter but her heart is starting to beat faster. Her lungs feeling the need for air, she wants to shut her eyes to muster up more but fears she could send them in the wrong direction if she loses focus. I won't let you die Kal goes through her mind just a bit further! I can make it! I can make it!

Clark watches as they`re nearing the surface, but thinks about the time, "get in here Kara! You've been out for too long!" that's when it hits him. "Kara… no don't do this!"

Her lungs are burning now for oxygen, biting her bottom lip in determination I'm not going to make it… but you will! There's no chance for me to get in, by the time he goes out the machine will have sunk further and will have filled with more water. I have to keep going! Just a little…

Adrenaline pumping through his veins now, he wants to smash his fist on the glass but knows it'll break and then he'll impede her efforts, he watches as they get closer to the surface at great speed now. "Hold on Kara!" he watches with baited breath.

No choice, the water fills into her mouth and into her airway as it burns for air but gets cold water filling them instead. She closes her eyes shut tight as darkness finally consumes her while the rate of speed she was moving at before slipping away propels her and the machine into the air. It soars high into the sky and lands with a hard thump onto land with her sprawled out on the sand.

Clark is knocked around on the inside with the water but once it is resting he kicks as hard as he can and the door bursts off, he climbs out quickly to find Kara just a couple feet away lying motionless. "No…" he runs to her side and rolls her onto her back, wiping water off his face and in the distance sees a dark figure running towards them. But his focus is on Kara, he places his ear on her chest and listens, willing his ear to hear a thud, but he doesn't.

"No! You can't die!" Clark yells and preps her for CPR, tilting her head up, pulling her chin down and begins compressions. "Don't you die on me, please don't die on me," he begs and presses onto her chest ten times before leaning down to pinch her nose close and sealing his lips over hers. Breathing two breaths into her before returning to compressions, "don't give up on me Kara, come on, you have to come back. I'm sorry I dragged you into this," he goes back to her mouth and breathes into her twice again.

He doesn't notice the dark figure has reached them and fallen to their knees on the other side of Kara, not until he looks up to make eye contact with Alex Danvers.

His attention goes back down to his cousin, the one who mentioned she once changed his diaper, he wants to smile at the memory in front of those fans of theirs. But all he sees is the grown up cousin of his that he may have just gotten killed, "come back to us! Please!" He goes back to her mouth and breaths into her two more times, straightening back up he presses down onto her chest.

Water jumps out of her mouth, Alex helps him turn Kara onto her side towards him to allow the water to come out easier. Choking out the water, emptying her lungs of all the fluid onto the dirt between them.

"What the hell happened?" Alex asks, feeling anger boiling up inside of her, she'd just found out from Winn that the two were going out and that it was because of a clue from Lex. This sent off alarms in her mind of a trap so she set out with a com in case she would have to call up J'onn, which she did as she was running over.

"I'm sorry Alex," Clark looks at her and is downcast, "it was a trap and if it wasn't for your sister, I wouldn't have gotten out alive," he watches Kara sit up. "We got stuck at the bottom of the ocean in that sphere, and one of us was able to leave before a wall of Kryptonite would keep the other inside. I thought I made an agreement with Supergirl to trade places when she couldn't hold her breath any longer… but she went the whole way up."

Alex looks at Kara, hoping she's okay after that scare and is looking forward to her explanation.

"If I went back in," Kara coughs, "more water would have gone in… and it would have gone back to sinking… taking longer to get to the surface," she wipes her nose and looks at Clark who looks ashamed of himself.

He rubs her back to try and help comfort her while Alex moves a strand of hair behind Kara's ear. Clark closes his eyes, "I'm sorry… I was panicking in the sphere and I hate when I can't do anything to help," he looks at her to see Alex is hugging her from the side. "You're my hero, you know that? And no more holding 'my job when I came here was to look out for you'," he adds.

Kara smiles at the comment, "not a chance, can't stop me from looking out for you anymore than you'll stop looking out for me cuz."

The End

I hope you enjoyed this! I may have one more for Clark and Kara but I'm starting to run out of ideas during this big break between episodes -_- I was asked to do a Kara/Alex 1st person centric but right now I haven't got any ideas. If you or anyone else has ideas I'll do my best to come up with more stories ^_^

-SLITH