I believe this was originally suggested by wanna-be-bold on Tumblr: AU where Kensi is UC and has to infiltrate something and get close to who they believe is the leader that turns out to be Deeks undercover.

Obviously I've stolen and pieced together bits from the show.

"Kens, you in position?"

"Yep," she responded, brushing her hair back from her ear to cover the movement of her mouth. The toe of her high heel caught on a loose stone and Kensi stumbled slightly before catching herself. Personally, a pencil skirt, blazer, and three inch heels wouldn't be her first choice for conducting a drug deal, but right now she was Bella Mendez.

They'd arrested Mendez after intercepting a message between her and a high stakes drug dealer. With a significant amount of pressure, Bella had given up her contact's name, one Max Gentry. Fortunately, Gentry had never met Bella or spoken to her, which meant Kensi could easily take her place.

Eric and Nell had found little about Max Gentry, other than that he seemed to have built a name for himself in the criminal world fairly quickly and had a suspiciously slim background.

Kensi, acting as Bella, had agreed to meet Gentry at a building that was once used to pack electronics. Since Bella had been dressed in business clothes when the arrested her, Kensi had chosen a pencil skirt, blazer, and stilettos. They were exactly the most practical, for quick getaways, but if Max Gentry was a "high class" drug dealer, she needed to look the part.

She approached the side entrance, stopping a few feet away, and pulled in a short breath.

"You good?" Sam checked and she hesitated a second before responding with an affirmative sound. Although going undercover wasn't new to her, Kensi was adept as Sam or Callen. Not that she'd ever tell them that.

"Just make him believe you're the Bella Mendez, make him believe you have what he wants, and get out," Callen instructed her. She resisted the urge to roll her eyes. At this point she had the plan, right down to why she was supposed to say, memorized.

Shaking her hair back, Kensi knocked confidently on the door, folding her hands in front of her while she waited. After approximately thirty seconds, the door slid open with surprisingly little noise and she was greeted with an scowling man with shoulder length hair. He was lanky and slightly awkward looking, probably no more than his early twenties.

"We're closed," he barked out, placing his body between her and the door so she couldn't see past him.

"I think your boss would disagree," she responded lightly, covering her surprise at being denied entrance.

"You got the wrong place lady." He squared his shoulders, suddenly appearing less scrawny and Kensi tensed as well, preparing for a fight. It was definitely not in the plan, but she wasn't about to be taken down by a wannabe thug.

"Frankie, let her in," a voice drawled, prompting the young man to step back enough for Kensi to slip by. She walked in slowly, carefully scanning the room. Two men sat at a card table, clearly in the middle of a poker game, a third casually heading towards her. It was too dark for Kensi to fully see him until he was right in front of her.

"Sorry about Frankie, he likes to tease," he said, in the same drawl she'd heard a minute ago. He held out his hand, smirking at her and added, "I'm Max."

He was nothing like she'd expected. Her eyes ran over him, quietly taking in the dark blue silk shirt and tailored pants he wore, before drifting up to his face again. His hair was blonde and slightly unruly, curling around his ears and he had a light beard.

Eyeing him coolly, Kensi ignored him as he clearly checked her out too, unapologetically staring.

"I don't appreciate jokes, Mr. Gentry," she replied in an aloof tone.

"Please, Max." He winked again, nearly drawing a smile from Kensi. "After all, we're going to be business partners, right?"

Damn it, she thought he was charming. Annoyed with herself, Kensi gave him an unimpressed look and crossed her arms.

"That remains to be seen. I only deal with serious buyers."

"Well, I am completely serious, Ms. Mendez," he said, his voice deepening although his expression didn't change. "During our earlier conversation you indicated you'd like make this a long-term endeavor. What's in it for me?"

"I can get you anything you want and in large quantities. I have contacts," Kensi explained, tilting her head as Max narrowed his eyes in her direction for a moment.

"Is that so?" His upper lip twitched, eyes darkening, and then he suddenly grabbed her around the waist, tugging her against him. Kensi gasped as he tangled a hand in her hair, kissing her aggressively. He stole her breath away and she froze, not resisting when he moved his mouth to her neck.

"I'm an undercover cop," he hissed in her ear, making her jerk at both sensation of his warmth breath brushing her skin and the unexpected message. "Quit ruining my op."

He made a show of running his nose along her jaw and then released her. Kensi sucked in a deep breath, trembling as he smirked at her, clearly pleased with himself even as his eyes flashed a silent warning. A flash of rage swept through her and Kensi pulled her arm back, punching him squarely on the jaw.

He jerked back, but managed to keep his footing as his men rushed to defend him.

Max-or whatever the hell his name was-waved them off, casually wiping blood from his chin.

"It's fine, guys." He nodded at Kensi, his gaze suddenly making her want to squirm. "I like you," he decided. "We can discuss the rest of this at my apartment. Frankie will give you the address."

"Just keep your hands to yourself," Kensi told him, lifting her chin defiantly. "The next time I won't be so gentle."

"I'm looking forward to it, Ms. Mendez."

As he walked away from her, Kensi knew that whatever was going on, she was way in over her head.