From the beginning, the balance of leadership in Atlantis evolved out of a struggle between civilian and military authority. The brief command of Colonel Samantha Carter - a scientist as brilliant as McKay and a comanding officer whom Sheppard respected more than any other he'd ever had - unified the scientific and military facets of the expedition in one office for a short while.

Ville, a sentient creature of energy, arrived in Atlantis on Carter's watch. No one was quite sure what to make of her but Carter knew her capabilities and made use of them. If Carter trusted her, Sheppard had no problem accepting her. McKay was won over instantly by Ville's interest in his work uncovering the secrets of the Atlanteans.

During an emergency, a cascading systems failure destabilised the city's power source : a single Zero Point Module, a device that extracts energy from a small contained portion of subspace. Ville's role during the crisis was to power the city's systems directly, including the Stargate, allowing them to safely remove and dispose of the damaged ZPM.

Atlantis was built to be powered by three such ZPMs; the expedition had only the one. The scarcity of these power sources, created by the Ancients over ten thousand years ago, left Ville as the de facto power source for the city.

When Wolsey informed Carter she was being reassigned and that he had been chosen to replace her, she assumed he'd been fully briefed by Stargate Command. Stargate Command assumed Carter would brief Wolsey on the power situation.

In his first official week on the job, Wolsey set himself a goal to schedule every member of the expedition for an interview, to take their measure as it were. The coy young woman with the enigmatic smile crossed his path in the halls several times; he merely smiled and nodded. Eventually he'd see her across his desk when her turn for review came.

In the meantime, he was having a little difficulty adjusting to the city's workings. Things the other inhabitants seem to handle naturally were awkward for him. The lights in his quarters would turn off at inappropriate times. Automatic doors failed to open and close for him as they should. When he used the transport system, he did not always arrive at his intended destination. At first, he would have a laugh at himself about it.

After several weeks, however, he began sniping about his technical difficulties to various personnel. He received little sympathy but began hearing a name. 'Oh, you should talk to Ville; she can fix that.' 'Just have Ville adjust it for you.' 'Ville might know, you should ask her.' He feigned recognition and re-checked the personnel records. He'd studied these files in detail before his arrival but there was no one named Ville amoung the members of the expedition. Maybe it's a nickname. Or possibly an elaborate prank or hazing - Wolsey knew he was not an entirely popular figure. Casually asked questions and fishing for details while trying to hide his ignorance soon turned into a game of "Where's Waldo?"

Most of the civilians seemed to know who she was but did not know a lot about her. Some of the military personnel said they didn't have that level of security clearance. McKay and Zelenka reacted as if Wolsey were having a bad joke on them. Major Lorne referred Wolsey to Colonel Sheppard because Lorne didn't think Wolsey had the necessary level of clearance.

Wolsey, ready to admit defeat, finally swallowed his pride and headed off to find the Colonel. Just then the coy young woman fell into step beside him.

"Good afternoon, Mr. Wolsey," she smiled brilliantly, "Looking for Colonel Sheppard, are you? He's on the East Pier, playing golf. I can show you the way if you like."

He demurred, "Thank you, but I think I can find the way."

"Alright then." She peeled off to join Teyla and Ronon down another hallway. As they receded from him, he heard Teyla greet her, "Good day to you, Ville..." and realised, he'd just dismissed the person he was looking for. While he debated whether to go after them, the doors of the nearest transport opened. Colonel Sheppard looked out, puzzled.

"Ah, Colonel, I was just looking for you-."

"That's weird."

"What is?"

"This isn't my stop."

"Oh. It's good to know it's not just meó."

"No, I mean, this never happens." Sheppard activated his comm, "Sheppard to McKay. What're you and Ville doing with the transport system?"

Wolsey pointed over his shoulder, "Actually..."

"Nothing. Why?"

"It just sent me to the wrong place."

"Weird. That never happens."

"That's what I said," the Colonel used his emphasized-patience voice.

"Are you sure you touched the right place on the map?"

"Yes. Rodney. It sent me to the wrong stop."

"Huh. Okay, we'll run a diagnostic. McKay out."

Sheppard gestured to Wolsey, "You should come, too."

Wolsey joined him, "So Ville works with Dr. McKay. Knows a lot about the city, does she?"

The Colonel gives him an odd look, "You could say that," wondering what the hell was with everybody today. He touches the control tower on the transport's map. When the transport opens again, they are in the control tower. "What do you have, Rodney?"

McKay gestures, walks and talks all at once while leading the way to the conference room, "Ville's already re-checking it. It's quite puzzling actually, we couldn't really find anything wrong..." The door panels open for him automatically. Sheppard follows and Wolsey manages to slip through as they begin to close again. He huffs and straightens his uniform jacket.

The coy young woman that he now knows is the enigmatic Ville sits on the table. Only now she seems older and not so coy nor cheerful. "Gentlemen. Thank you for coming." Her tone is chilly.

Sheppard takes a wild guess, "There's nothing wrong with the transport system, is there?"

Clueless, McKay responds, "I told you that never happens."

"Now, see here, young lady-," Wolsey steps forward.

She interrupts him. "So. Now you have time to speak with me, Mr. Wolsey."

"Uh-oh," McKay mutters. Sheppard shares McKay's sneaking suspicion, "What seems to be the problem?"

Without taking her eyes off Wolsey, she says, "I know everyone in this city. Work well with each of them. There is mutual respect and even admiration."

Wolsey tries to reassert control of the conversation but Sheppard takes his elbow. "Ville, would you give us just one minute?" He steers Wolsey a few steps away, a symbolic gesture to allow Wolsey to save what little face he has left. "You do know who she is, right? Tell me you know."

"What do you mean? That she works with the city's support systems? That doesn't excuse unprofessional conduct or bad behaviour."

Sheppard rubs his face. "She doesn't just work with the city's systems. She is the city's system. What you see there is an avatar."

"An avatar? Of what?"

"Okay, long story short : her father was an ascended Ancient. He created these three...children of pure energy. She's one of 'em - an independent, self-aware entity who happens to have saved our asses last year. Didn't you read the report?"

Wolsey pales at the thought that he may have offended an Ancient, "No one briefed me..."

"Never mind. I'll introduce you. Just be polite and apologetic." Sheppard steers him back. "Ville, this is Colonel Carter's replacement, Richard Wolsey from the IOA. Mr. Wolsey, this is Ville. She keeps the city systems powered and monitors the safety of everyone on the base."

McKay adds enthusiastically, "Oh, she does way more than that. She monitors the planet's atmosphere for anomalies that might affect the city - planet-wide hurricanes, marine quakes, that sort of thing. Oh, and she can track objects beyond the solar system, augmenting the long range sensors. It's quite fascinating, actually, you see-."

Ville lays her hand on McKay's arm affectionately. "That's high praise coming from you, Rodney, thank you."

"Oh. Well, you're welcome." He starts to leave then turns to add, "You should see her sift through the databases, it really is amazing..."

Sheppard uses his listen-to-your-elders voice, "Rod-ney."

"Yes, yes, well, if you'll excuse me, I have work to do." The door panels open and close for him. A thought occurs to Wolsey. Pointing at the doors, he asks, "Did you-?"

"Yes, I do that, too. You may have noticed, Dr. McKay has two speeds : fast and faster. And he doesn't always look where he's going nor care what's in the way."

Sheppard asks, "Wait a minute, you open doors for him?"

She counters, "And when have you ever had to wait for flight clearance from the jumper bay? I like doing little things for each resident of the city to make them feel at home, safe and welcome," she throws Wolsey a glance then quips to Sheppard, "God is supposed to be in the details after all."

"So you're the reason my lights have been going off and doors close in my...face...," Wolsey sputters, "How rude!"

Sheppard mutters, "Politely-"

"Rude? You arrived unannounced and have been walking around my city for weeks without so much as an introduction."

"Your city? Now see here, I am in charge! There was a memo!"

"Yes, you left it on my server!"

"Your server?"

"The safety of this city and its residents are my responsibility; I am a Guardian..."

"Whoa, whoa, whoa, hold up there," Sheppard breaks in with his temper-soothing voice, "He hasn't read the file yet."

"What file?" Wolsey demands.

Sheppard uses his I-can-shout-louder-than-you-so-don't-even-try voice, "The file I'm gonna ask General O'Neill to grant you temporary clearance to read."

Hotly, Wolsey answers, "I assure you, I have the highest level of security clearance. I have total access to everything related to the Stargate program and the SGC."

"No. You don't," Sheppard settles his hands on his hips in a matter-of-fact stance.

"What could possibly be higher than 'Above Top Secret' clearance?"

"I'm not at liberty to tell you - you don't have the necessary clearance," Sheppard switches to his if-you-keep-asking-stupid-questions-I'm-going-to-have-to-shoot-you voice.

"What?"

Ville inserts herself into the conversation again, "Oh, come on, John, that's just a bit of 'Who's on First?' Even I wouldn't resort to that."

"First of all, 'Who's on First?' is a classic." Sheppard waggles his finger at her.

"Please stop before you embarrass yourself. Again," she teases him. "Now, Mr. Wolsey. You are in charge, I presume, of the expedition personnel, yes?"

Wolsey answers emphatically, "Yes. Yes, I am."

"Good. I am in charge of the city. For all practical purposes, I am Atlantis. You and the members of your expedition are my residents."

Sheppard whispers to Wolsey using his trying-vainly-to-lighten-the-mood-since-you're-probably-a-little-freaked-out-right-now voice, "She's sorta the Home Owners Association."

Ville nods. "And you, sir, have moved in without being properly vetted."

Pale, Wolsey turns to Sheppard. "What is that supposed to mean?"

Sheppard grimaces, "You should probably keep your dog out of her yard."