Disclaimer: Characters etc belong to CBS and the show's creators.

Author's Note: Set post episode 6 "Sabotage" where the FBI investigate a series of recreated accidents involving railroad negligence. This picks up where the episode left off.

One

Charlie's animated voice could be heard from the table in the next room as he continued regaling David and Terry with examples of the artistic application of complex algorithms. Terry had made the made mistake of telling Charlie she didn't see how math related to the real world, and they were now paying the consequences.

His explanation of the Fibonacci sequence prompted David to mention its inclusion in The Da Vinci Code, which had set Charlie off a new tangent – mathematical code in art. Charlie had found a scrap of paper and pen and was scribbling furiously, almost maniacally, as he detailed the inaccuracies in the popular novel. David was shaking his head as Terry groaned – it was going to be a long night.

"Aren't you going to rescue your partner?" Amita asked Don, as the two of them watched from the dining room.

"Terry knows better by now than to bait Charlie like that," Don said, taking a sip of his beer. "He bailed her up one Thanksgiving for three hours when she made the mistake of questioning the futility of Minesweeper. P vs NP, for God's sake…"

He shook his head at the remembrance.

"In that case she deserves everything she gets." Amita smiled good naturedly.

"Of course, you mathematicians stick together."

"I'm not exactly in Charlie's league, but I'll take that as a compliment."

"Well, you do a pretty good imitation of it. You've been a great help on these cases." Don tilted his beer bottled towards her, and Amita clinked hers with it. "Cheers."

"You and the other agents are the impressive ones," Anita said. "It's amazing to be around."

Don looked at her through half-closed eyes. "It's okay, I guess."

"Okay? Don, you save lives, you protect innocent people from being hurt, you catch the bad guys… These are not insignificant things."

He shrugged in a non-committal way, but was pleased nonetheless. There were worse things in the world than impressing beautiful grad students. But Don had to remind himself this was Amita, a woman he suspected his brother had more than a passing interest in, even if it was unlikely Charlie would ever do anything about it.

Don had certainly noticed Amita, after she started working with Charlie. Not only was she intelligent and funny, she was warm and relatable where Charlie's other colleagues – good-natured Larry included – were not. And she was a knock out. Don couldn't ignore that simple fact. Yet another reason why he questioned how his little brother failed to make any sort of move on her. Typical Charlie.

"So, you and Terry… Charlie said the two of you used to date?" Amita said casually.

Don frowned slightly, not expecting the question. Immediately he grew annoyed at his family's propensity to discuss his history with his partner. Why else would she be asking?

"Many years ago, when we were at the Academy together."

"So why aren't you together now?" Amita asked innocently, as David and Terry's debate with Charlie in the next room escalated.

"Did my dad put you up to this?" said Don, with an exasperated sigh.

"No, answer the question."

Don rubbed the cool beer bottle against his temple. The topic made him weary, he was growing tired of everyone's assumption that Terry and he should be together.

"Because we're partners… it's not exactly well received. Not to mention awkward, I mean we work together every day. That kind of complexity cannot be a good thing."

Amita nodded, smiling slightly as she looked at Charlie.

"What?" Don countered. "What are you smiling at?"

"Nothing…" she replied, smothering the expression.

"Then what about you and Charlie?"

Amita grinned. "Oh, here we go. Not you too."

"What? Dad's on at you two as well?"

"You could say that."

"So…"

"So, it's the same deal. We work together – well, he's my thesis supervisor. The rules against dating are there for a reason."

"But if not for university rules…" Don prompted.

"If there were no university rules," Amita said slowly, contemplating her answer, "your brother would have girls lining up outside his office door. He's considered quite the campus catch, you know."

"Wow, that was a really evasive response, Ms Ramanujan."

"Thank you, Agent Eppes." Amita smiled again, but this time she was looking at Don. "So, what if the FBI allowed you to date your partner?"

Don sighed, looking over at Terry. It wasn't the first time he'd imagined such a scenario, but he knew no good could come of it. He and Terry had been great together, but things were different now. While they were working in the same office – partners, no less – there was no room for any more.

"Honestly, I think sometimes it's best to leave things in the past. It's hard to recapture something that was lost a long time ago."

Amita nodded slightly, and went back to looking at the people around the table in the other room. Don took a last swig of beer and set the empty bottle on the table. His earlier celebratory mood had left him and he just felt worn out from the day's events. The notion of going home to his empty apartment wasn't exactly comforting either, but he could barely remember what it was like to have someone to go home to.

"So, do you ever take a break from saving lives and catching bad guys?" Amita asked suddenly, breaking the silence.

Don had stood up to stretch his back, deciding to crash here at the house rather than heading home. "Well, let's see," he mused. "I barely remember what my apartment looks like in daylight, and my father likes to remind me how little time I spend with him despite moving back to LA to be near my family. I think he's hinting I may be a workaholic. Why?"

"I was just wondering if you'd like to have dinner some time."

"What!" he laughed. The word was out of his mouth before Don knew what he'd said.

Amita's cheeks flushed slightly.

"Are you asking me out on a date?" he asked, puzzled.

"No," Amita said stubbornly in reply. "Well, I obviously didn't do a very job of it if that's your reaction…"

"I'm sorry," Don said quickly. "I just need to catch up… I thought we were just talking about you and Charlie."

"No, you were talking about Charlie and me… I was asking if you were romantically involved with your partner." Amita tucked her hair behind her ears. "Listen, it's no big deal, Don. Forget about it."

She stood up to join the others.

"Hang on, wait a second." Don reached out an arm to stop her. "I'm not trying to be a jerk, it's just… it's not every day a… beautiful woman asks me to dinner. Let alone someone who I always thought had a crush on my little brother."

Amita smiled, not unkindly. "I didn't say I'd be there lining up outside his office, though, did I?"

Don's mouth was slightly agape as Amita turned and walked into the other room. She took a seat at the table and smiled at Charlie and the agents. Charlie immediately enlisted her to join him in browbeating David some more. Don continued to watch her, slightly stunned, until Terry escaped from the room and begged him to give her a ride home.