"What'cha got, Ducky?" Agent Gibbs asked as he entered autopsy.

"Jethro…" Dr. 'Ducky' Mallard looked up. A man was laid across the metal exam table, bloated and gray. Ducky tapped the body's muscular arm. "The poor fellow's cause of death is quite simple…" The doctor moved around the body, prying open an eyelid and frowning.

"Duck…I'm waiting."

"Sorry. But it's extraordinary, really. It seems our unfortunate petty officer…drowned."

"Drowned?" Gibbs barked. "He was found in his living room."

The doctor hummed his agreement. "And yet there is no doubt that the poor fellow succumbed in such a manner. However, that in itself is not so unusual. Why, when I was studying in Edinburgh, a professor in the literature department managed to drown in a bucket containing only half a centimeter of…"

Gibbs cut him off. "The point, Duck."

"Right. Well, the strange thing about our victim is that the amount of liquid in his lungs and the effects on the soft tissues of his body are more consistent with submersion in a large quantity of fluid, not a happenstance drowning in a puddle or even bathtub. And I doubt there were such depths of water inside our young officer's home."

"So he wasn't killed in his house."

"That, Jethro, I'm afraid is outside my area of expertise." He sighed looking down at the body. "However, I sent Mr. Palmer upstairs to our brilliant Abigail for analysis of the fluid from the lungs. Maybe that will provide you with some answers…" The doctor glanced up. Agent Gibbs was gone. He sighed, turning towards the corpse. "I suppose that just leaves you and me. Now, young man, how did you manage to get yourself into this unfortunate state?"

**

Gibbs heard voices as he entered Abby's lab. His forensic scientist sounded put out.

"You're not here." She said. "I don't see you. I don't hear you. I am the only person in here."

"Look…" Said another voice, young and male. "Ms. Sciuto, it's just for a few days. I need this for my graduate work." He sounded earnest. "If you would give me a chance…"

"Okay, you look, whoever you are…" Abby didn't like strangers in her lab. She was territorial like that.

"Sam. I'm Sam." Exasperation was evident in the young man's tone.

"Whatever." Abby didn't seem to care. "I don't work well with others. I don't care who gave you permission to shadow me. If I can't make you leave, I'm going to pretend like you don't exist."

Gibbs rounded the corner. Abby's goth wear was spectacularly black and red. She had on four inch platform heels which put her close to Gibbs height. The guy she was talking to stood slightly hunched over like he was hiding his height, and he still had several inches on them both. He was dressed cheaply in jeans and several layers of shirts. He looked up as Gibbs entered the room.

"Gibbs!" Abby shouted in a relieved voice as he walked up. She ran to him and put her arms around him. "You've got to do something. I can't have someone stranger messing in my lab."

The young man, mid twenties Gibbs guessed, smiled sweetly and stepped towards him. "It's just for a few days…" He fumbled in his bag, pulling out a stack of paperwork. "It's important...for my degree. And I have permission. I promise I won't be any trouble…" He turned towards Abby. "Please, Ms. Sciuto…" He smiled again.

"No dimpling at me. That's not going to work." Abby looked at Gibbs – the plea evident in her face. "Make him go, Gibbs."

Gibbs peered at Sam. "I wasn't notified anyone would be working with Abby."

"Um…yeah." The young man fumbled with his shirts. "They didn't think you'd agree?" His voice sounded uncertain.

Gibbs stared at him and the young man fidgeted under his gaze. He seemed harmless enough. But his layers looked like they hid a muscular form. Gibbs grabbed the papers. "These look in order, Abs?" Gibbs said. Abby nodded, frowning. Sam shifted nervously in front on them. "Hmmm." He'd get them rechecked.

"Uh…Okay. I mean…yes sir. I can stay then?" Sam waited.

"Yep." Gibbs said.

Abby huffed, crossing her arms. "Gibbs…" She said, unhappiness twisting in her tone.

Gibbs turned towards Sam. "As long as you can convince Abby to keep you by the end of the day." He said. Abby grinned in Sam's direction, triumph written in her features.

The young man grimaced. "But…I have permission…"

"As long as Abby agrees..." He said.

"Yes sir. The end of the day." Sam shook his head. Gibbs turned to focus only on Abby. "You got anything for me on the water sample, Abs."

"Gibbs." Abby said, her tone turning playful now that she had permission to dismiss Sam later. "Palmer brought me the sample fifteen minutes ago. And since then I've been dealing with…" She waved in Sam's direction. "This."

The young man remained judiciously silent. Gibbs was impressed he knew when to keep quiet.

"Abs. I need to know everything I can about how and where the petty officer drowned."

"Patience, Gibbs." Abby smiled. She patted the large instrument against the wall. "General Mass Spec has been grumpy this morning."

"When, Abby?"

Abby sighed. "Maybe three hours." She cut a glare at Sam. "Assuming no one gets in my way."

"Three hours?" Gibbs huffed. "Okay." His phone rang as he turned to go. "Gibbs." He answered. "Yeah. Where?" He paused. "On my way." He turned back to Abby.

"Just get on it, Abs." He said, sounding harsh.

"What happened, Gibbs?" She asked. Sam looked curious beside her.

Gibbs frowned. "We've got another one."

**

Three hours and one dead, bloated marine later, Gibbs strode into the forensics lab holding a Caf-Pow. Abby was smiling up at Sam who was saying something about a protective tattoo.

"Whatcha got, Abs?" Gibbs said. He spared a glance at Sam, surprised his scientist seemed to be warming to him. Abby's face lit up when she saw him.

"Oh, Gibbs, I've got a lot." Abby reached for the large cup, but Gibbs kept it out of reach.

"Like?" He asked.

"Like the water in his lungs was filled with various freshwater protozoans and algae. That basically limits the place where he drowned to ponds and lakes in the areas. Based on the types of critters we found, it also would be a stagnant or still lake. So we can eliminate most of the rivers or streams in the areas."

"Okay. And?" Gibbs said.

Abby shot Sam a brilliant smile. "And. There's a paper plant near the petty officer's home. Based on a fifty mile search area, we extrapolated the expected amounts of certain nitrates and phosphates per area away from the plant. Then we compared that to the amount of those same chemicals in the sample from the lungs and matched it up to a current hydrology study in the area."

"Which means what?"

"Which means…" Abby said motioning to Sam. He pulled up a map on her computer screen. "Sam and I have determined two possible drowning sites for the victim." She pointed to the map. "Here or here."

Gibbs handed her the drink. "Good work, Abs."

A ringing sound came from Sam's jacket. "Oh. Sorry." He said pulling it out. He glanced at it and then at them. "I…ah…need to take this. It's my brother and see he's…well." He looked at them both again. "So, can I come back?"

Abby gave him a firm head nod. "See you tomorrow, Sam." She said

Sam smiled. "Yeah. Good. Bye, Abby." He turned nodded towards Gibbs. "Agent Gibbs."