By Any Other Name…

Summary: Giles gets a blast from his past during a joint operation with a couple intelligence agencies.

Timeline: totally AU BtVS'verse. Well, not totally…just for one character. Post- 'Need to Know' for NCIS.

A/N: People might hate my pairing, but I couldn't help myself.

Thanks to my betas: nope

Disclaimer: BtVS/AtS characters belong to Joss Whedon/Mutant Enemy. NCIS characters belong to Donald Bellisario, Don McGill and CBS Paramount Television. I claim no rights to any copyrighted material. Please do not copy or take this story without my permission.

NCIS Bullpen

"So, according to Director Vance, we are expected to offer our full cooperation with these two groups," Gibbs explained to his team in a growly, pissed-off tone. "Obviously, we've already had some dealings with MI5, but nobody has explained to me why this G2 is being given access to our investigation."

A soft voice spoke up from behind him, "Actually, it's 'G-Squared', and we're here because we have classified information that will help stop the terrorists from being able to complete their mission."

Gibbs turned around to find a young blonde woman standing beside a man about his age. "Can I help you?" he asked, clearly trying to impress upon them that he wasn't happy with their presence.

To his surprise – and his team's utter shock – she started giggling. "Giles, he's trying to scare us! That's so adorable!"

"Buffy," the man reprimanded her, "Remember that we are supposed to behave in a professional manner here." He held his hand out and introduced himself and his companion, "My name is Rupert Giles and this is my partner, Buffy Summers-Giles. May I assume that one of you is Agent Gibbs?"

"I'm Gibbs," the team leader affirmed, shaking the offered hand, then repeating it with the young woman who was attempting to stifle her amusement.

"I apologize for Buffy's mirth. She tends to get amused whenever anyone tries to intimidate her. Well, that's not entirely accurate. Most of the time, she is amused," Giles said, then cut himself off before he could reveal too much.

Tony couldn't help himself; he just had to ask, "What about the rest of the time?"

"I get angry," Buffy answered. "And when I get angry like that, the people trying to frighten me tend to get hurt or dead. To be fair, they're usually trying to kill somebody I care about, though."

"What's G-Squared?" Tim asked, hoping to break the awkward silence that settled on the room after that announcement.

"It's a couple things," Buffy replied. "Professionally, it's Guardians Group, but personally – and I think the bigger reason everyone voted on it – it's Giles and Giles…me and him," she finished gesturing at Rupert. "Faith and Xander have a tendency to call Giles 'G' or 'G-man' or something like that, so when we got married, they laughed about us being two Gs. Then Willow, Dawn and Andrew got involved and thought it was more like G to the power of two because we are stronger together."

"I don't think they need our personal history," Giles complained softly.

Buffy looked up at him and blushed in embarrassment. "Oops, sorry?"

"As amusing as this is, we should get up to the conference room and start working on the problem," Gibbs interjected.

"Yeah, let's go catch the baddies so we can do some sightseeing!" Buffy agreed enthusiastically.

"These people are supposed to be able to help us?" Ziva asked Tony quietly as they followed the strangers up the stairs. Tony just shrugged in reply. While they might seem like an unusual pair, he'd been surprised too many times in the past to let himself be fooled by appearances this time. They had the Director's approval and that had to mean something.

Conference Room

"Inspector Challis?" Gibbs called out as he entered the room. "The members of G-Squared are here. May I introduce Rupert Giles and Buffy Summers-Giles? This is the liaison from MI5, Inspector Andrew Challis."

The man who had been sitting in a chair, looking down at some papers suddenly shot out of his seat with a pale expression on his face. "Hey there, Ripper. Didn't expect to see you again…ever."

Giles' response was less than eloquent. "Bloody hell!"

"I take it you've met before?" Gibbs asked. This could be a problem if there was some personal history between the two men. Lord knows that he never enjoyed working with some of the people he'd been forced together with in the past.

Buffy also noticed the tight expression on her husband's face and dropped into a protective stance slightly ahead of him. "Who is he, Giles?"

"Somebody who shares a particular tattoo with me," Giles answered cryptically. It was enough to clue Buffy in as to the man's identity – sort of – without going into specifics in front of strangers. "I'd like a moment alone with Buffy and Inspector Challis, if I may." His tone made it clear this wasn't a request, but a command.

As soon as the door was shut behind the stunned NCIS team, Giles glared at the MI5 Inspector. "What are you doing here, Ethan? And what is with the name change?"

"You weren't the only one who started over after Randall's death, Rupert," Ethan/Andrew shot back. "You had the Council to run back to; I had my mother's family. Once I promised to clean up my act, Grandfather Challis gave me his name so I could put my demon-raising days behind me. Andrew is my middle name."

"You'd never be able to give up worshiping Chaos," Giles accused. "It was like breathing to you!"

Ethan snorted. "You don't think the world of intelligence is chaotic? And don't forget, the other side of that coin is order. Janus has two sides and I worshiped Janus…still do, in fact. Now I just do it in a slightly different manner. Now, can you and your little missus there accept that? Oh my god! Is she a Slayer? Your Slayer?"

"Remember, Giles, we're supposed to act like professionals here," Buffy couldn't help but tease her Watcher by throwing his own words back in his face. Then she turned back to Ethan and gave him her best Slayer Glare. "Make no mistake, though…if you do anything to cause trouble for my husband – or the world – I will make you regret being born," she threatened convincingly.

"I promise that I'm a productive member of the human race now," Ethan vowed. "On the name of Janus. I take it that your presence here indicates some kind of supernatural involvement? How are you keeping that from these people?"

"We're treating this like a group of terrorists," Giles answered, feeling better that Ethan- no, Andrew was sincere since he swore on the name of Janus…the equivalent of a stack of Bibles for some people. "The fact that they are a radical group of half-demons is beside the point; they are still committing an act of terrorism. If we're lucky, they won't show themselves to be non-human when they are apprehended."

"You just jinxed us, you know that," Buffy pointed out with a smirk. At least this time she could say it was Giles' fault they had to give the spiel. The betting pool back home would go crazy when they found out.

A/N: Obviously, this Ethan never came to Sunnydale. I figured, why couldn't he grow up like Giles did? Someday, I might have a different take on the characters played by Robin Sachs, but in honor of his death, I thought this was a little more appropriate.