The Chief of the Boat knew the crew better than the skipper did. And he was much better at reading people as well. From the minute those two NCIS agents had come aboard, he was absolutely certain there was something between them that wasn't appropriate.

The fact that there was even a woman aboard said it all. Women, as a rule, were not allowed on board submarines, and yet here was Agent Caitlin Todd, standing just a bit too close to her male counterpart, Agent Gibbs. There were rules for a reason, after all.

They had taken over the sub essentially, and he was required to babysit their five suspects. This of course did not bother him. He did as he was told. He babysat, and he kept his eyes and ears open. He kept those suspects from talking to each other, and he watched every second of interaction between the two agents.

What bothered him was the clear fraternization between the two agents. He had stayed just a second too long, and watched as Agent Gibbs explained a term to Agent Todd, and touched her hand. Neither had noticed him leave, which further proved his point. Well he'd have a word for Commander Peters and the Director of NCIS both once they docked.

For now, it didn't matter. What mattered was that they solved the damn case, preferably without someone else dying in the process. He had no doubt that if something happened aboard the sub, Agent Gibbs' priority would be saving Agent Todd. The COB had figured it out from the way he'd caught them looking at each other.

And then came the order: emergency blow.

XNCISX

"You really can be a bastard you know that?" Kate was pissed at Gibbs, and somehow he didn't mind. He was mildly concerned, as she could probably kill him in a few different ways, but at the same time he found the way her eyes had filled with fire to be very attractive.

"Yet I fought so you could get on the sub. I defended you to Veitch."

"Because you knew I was more qualified. I was in the Secret Service, Gibbs. Tony will never be as qualified."

He groaned. "It's not just because you're qualified, Kate!"

"Of course it is. Why else would you…?" she trailed off, watching him.

"If you don't know by now, Katie, I should have taken Tony. Or that greenie agent McGee from Norfolk."

"What the hell are you talking about?" she asked, annoyed.

"Seriously? All that profile training and ya still don't get it?"

She opened her mouth to continue, when suddenly the sub titled alarmingly, and she fell against him, dizzily, until the two of them slammed against the wall. His body was pressed quite firmly against hers, and he had his arms around her. He looked down, as if to ask if she was okay.

She nodded, before asking, "What was that?"

"Emergency blow." He looked away, willing himself not to care about the fact that his beautiful younger subordinate was pressed against him, and was likely to remain that way until the sub levelled again. He couldn't help it. He leaned down and took her face, kissing her. It started off gentle, as Kate stiffened in surprise, before melting against him. He felt the exact second she had given up resisting, and embraced this rather unorthodox method of ignoring whatever emergency had led to the emergency blow. His hands moved from holding her face, tangling in her hair, and he would swear until his dying day that she actually sighed into his lips. And then he heard the door open, and pulled away.

She looked mildly dazed, but grinned up at him anyway.

It was the COB, who was looking at both of them suspiciously.

"Wow," she muttered, and Gibbs had to grin. He hadn't been expecting that, and had half expected her to jump away at the first chance she got, calling him a bastard and reporting him to HR. But she was still against him, though the sub was getting closer to being level.

"Yeah," and he couldn't resist teasing her, it was too easy. "That's what they all tell me."

She smacked his chest, and pulled away, but he could see that underneath her unimpressed façade, she was actually incredibly happy. And that assuaged some of his worries.

"The skipper wants you."

They walked away, him leading, and then as he passed the COB, he noticed the smirk on his face, and his heart sunk a bit. Had he seen? Because Gibbs had rule 12, though he'd never told Kate, and also if Kate wouldn't report him… the COB might. That was enough to dampen whatever euphoria Gibbs had gotten from their kiss.

He only hoped that if either one of them got in trouble, it would be him.

XNCISX

Oh, he had them. He had walked in, just in time to see them going at it during the emergency blow. He had seen the alarm in the older agent's eyes and wasn't quite ready to relinquish that control. In fact, the steward who had brought them the ice cream had reported that both were in considerable levels of undress when he had brought the ice cream in, and the first few buttons of Agent Todd's shirt were undone. It was all the COB needed to prove his theory.

They were secretly sleeping together. And the COB felt very uncomfortable ever eating or sitting at the table in the Ward room. At least not until it had been properly sanitized. Clearly not one of the higher-ups knew about the hanky-panky going on between Agent Gibbs and Agent Todd. Christ and he was at least two decades her senior!

Of course, between getting rid of the body, and getting the ice cream back in the freezer before night fell, the COB had other priorities on his mind. And then another problem arose. Quarters were very tight on a sub, everyone in the Navy knew that. So he regretted it immensely, but he had to let the two NCIS agents bunk together.

And then he reassured himself that he was doing the right thing, because surely once he reported them, they wouldn't have another chance to be together. It still wasn't really a reassurance, and he almost felt bad for them.

Gritting his teeth, he kept his mouth shut as they closed the door to their shared berth.

There would be time for reporting them later, he was sure.

XNCISX

Kate had changed into a basketball jersey that Gibbs had learned was all she wore to sleep. It was just as well, considering that the air con was not back on yet. He was watching her brush out her hair, and then sat down on his berth, sighing. It wasn't very comfortable. Another glance at Kate made it worth it.

She looked up at the noise he made, "You good Gibbs?" a smile played across her lips as she said his name, and he was reminded that she was gorgeous- not that he needed reminding.

"Bed. Not comfortable." He said, but he was grinning.

She sat down on her berth, and grinned at him. "Then share with me."

His mouth dropped open, "What?"

"Are you already going deaf in your old age?" she teased. He knew for a fact that he was only eighteen years her senior. Yeah, that was enough, but making jokes about old age wasn't very fair. "I said share with me."

"No, Kate, I couldn't."

"If your bed feels like a rock, then you won't get any sleep, and I'll have to put up with your grumpy attitude all the way back to DC, which I don't want to do."

"If we get reported, I blame you." He gave in, quite graciously, he thought. He walked over, and said, "It's a bit narrow."

She shrugged. "We can squeeze." And then she paused, not looking at him. "Are we going to talk about it?"

"About what?" That stopped him in his tracks.

"The emergency blow. How you kissed me."

"Nah. We can talk about it tomorrow. Ya look tired, Kate. We should sleep."

She nodded, and reached over, flicking out the light, before they crammed themselves into the narrow bed. They were practically spooning, and he couldn't help it. He kissed the back of her neck, and murmured, "Good night Katie."

"Night Gibbs."

It was some time before the two of them finally fell into an exhausted sleep. They never again spoke of what had happened on the submarine, though both carried it with them for the rest of their lives.

And the COB? He never did end up reporting them.