I don't really like seeing Jack as a bad guy, but I had the idea so I wrote it out.

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"I see five" She hears Sams voice through her coms.
They were getting ready to breach a warehouse, owned by a terrorist.
She signaled to Deeks that she was going to the back door, and he nodded.
"Breaching." She heard Callen say.
She banged open the back door expecting to be engaged in a full-blown gun battle but instead found herself in a small empty room, she could hear the bullets flying to and from, each round of bullets, fewer guns were firing, she swung open the door of the small room, and held her gun up high, walking to the sound of the bullets, there was only one man left standing with his automatic weapon keeping Sam, Deeks, and Callen, help up. She had a silent approach since the man's back was to her.
"Drop the weapon!" She shouted sternly.
The man knelt down, put his weapon on the ground, and turned around slowly.
But Kensi's mouth opened in shock when she saw the shooters face.
"Jack.." She said, not a statement or a question.
"Nice to see you again, KayKay." He said smugly.

"You good, Kens?" Deeks asked her in the boatshed with worry written all over his face.
"I'm good, let's break this guy." She said as she walked into the integration room, and closed, or rather slammed the door much more forcefully than needed.
"Why were you in that warehouse?"
"Wow, so Kensi Marie Blye, a federal agent. So what, do you go 'Blye...Kensi Blye'?"
She closed her eyes and took in a deep breath.
When she opened her eyes, Jack had on an infuriating smug smile.
"Kens, you good?" Deeks asked tenderly.
"I'm good, thanks." She said, looking up to smile at him, but then bring her face back down to Jack with a dead stare.
"Oh, that's just adorable, you two have this unbreakable bond."
She shifted a little bit uncomforbly in her chair, much to Jacks pleasure, so he continued.
"So what, this is was your dream career choice, you know after marine housewife. Well, I mean I could picture you a federal agent, but not a very good one, but I mean I guess your not a good one because they pair you with this wannabe cop slash terrier, does he even own a hairbrush?"
"I do own a hairbrush, but that's what I keep trying to tell Kensilina here, my hair is styled-by-pillow." Deeks countered in a childish manner, but still matching the hate in his voice.
"Well." He said, turning his attention back to Kensi. "You found a good one here, protecting you even when you don't need help, or when you don't think you need help because let's face it, you couldn't do a thing without anyone's help."
That was it, that pushed her over the edge.
She grabbed his shirt to pull him closer to her face in the roughest manner possible.
"Let's get one thing straight, you do not know me anymore, or what I have done without your selfish little self getting in the way and messing up everything I can and could have done, and don't ever ever talk about my job, because from the looks of it I'm doing a better job then you EVER could." She practically yelled in his face.
"Kensi.." Deeks said as he ever so gently removed her hand from his shirt.
She stood up and walked out of the boatshed.
"Pathetic" Jack said under his breath.
Deeks grabbed Jacks shirt pulled him out of his chair, onto the wall, pulled out his gun, and stuck it under his chin.
"Say it again, say it to my face." Deeks said forcefully.
"Make me." Jack said matching his forceful tone.
Sam and Callen came busting in ordering Deeks to put the gun down.
After a little while, he lowered the weapon and walked out of the boatshed.
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I don't think I'm going to continue this...I might so please give me your thoughts. I tried my hardest. e.e