Stereoisomers: two molecules that are related to each other by a reflection: they are mirror images of each other.

Jack replied, "I know you,"

"Lots of people do."

"That's a switch."

"What?"

An apple came to rest at Jack's feet. He picked it up and smiled, remembering. "You taught me about wormhole theory."

"Ah." Sam nodded in recognition. "I do know you. You're the guy they found in Egypt."

"My reputation exceeds me."

"How did you know where I live?"

"I've known for years, Carter." He said it casually, as if she shouldn't be surprised at all.

The tone of his voice disturbed her more than his words. "What can I help you with?" She noticed that he hadn't made a single step up the walk- he just stood there with the apple in his hand. But Jack knew all about trespassing, concealed weapons, justifiable homicide and what a great shot she was; and he wasn't about to give her a reason to show just how much she knew about those subjects, too.

"A couple of things. I need to convince you not to help out with the stargate, and I need you to get me out of here."

Sam studied him carefully. Just because he's handsome doesn't mean he's not crazy.

"What can I do to convince you?" Jack tossed the apple in the air and caught it. He spotted the garage. "You like motorcycles."

"That's on my NASA bio."

"It's an Indian. Very rare. You also speed but the cops tend to give you warnings- with their phone numbers written on the back." Jack suppressed a grin. "Not that you ever call them back."

"How do you know about that?" she looked up, a bottle in her hand, eyes wide.

"I know a lot about you, Samantha Carter." Her name caught in his throat as Jack suddenly wondered how the hell he ever thought he'd be able to deal with this. He should have waited, should have given it more thought. What it all meant, what it would be like instead of running to her as if she were his salvation.

And Jack never even considered that she might prove to be his downfall.

She straightened up and studied him for a moment. "Come in, then. But at least pick up those apples."

"Yes, ma'am." Jack picked up the fruit. "As long as you leave that gun in the coffee table. I'm not going to hurt you."

She stood with her handle on the doorknob, and looked at him for a long moment. "No you're not."

Jack didn't know if that meant she trusted him or that she could kick his ass. He hoped both were still true as he followed her into the house and then into the kitchen. He almost opened the pantry to put away the apples because she didn't like them in the fridge, but he stopped himself and laid them on the counter.

She stood warily on the other side of it. "Why don't you have a seat in the living room?" Sam kept an eye on him as she stowed the apples in the pantry.

Jack walked over to a chair and sat in it as if he'd done it a hundred times before- which he had. She observed him, her head tilted to the side, trying to figure out how to talk to a delusional man who still seemed completely logical, knew things no one should have known, and understood theoretical astrophysics that a flyboy like him shouldn't have a clue about.

Meanwhile, Jack watched her break his heart into little pieces.

Finally, she sat down opposite him, took her semiautomatic out of the coffee table and laid it on the armrest, her hand resting on top of it.

"So, Jonathan O'Neill, what's the story?"

"It's Archer. I had to change it since evidently I'm dead."

Sam shook her head. That was it- classic mania with delusions of grandeur. She wondered how the psychiatrists could have missed it. "So now you're the captain of the Enterprise."

"Kirk was too obvious, and Archer's better looking, don't you think?" Jack smiled. "The cloak-and-dagger types told me to keep my first name since people slip up with a new one. Besides, I go by Jack. No one noticed."

Sam smiled. "Okay, Jack O'Neill," Sam waved her hand, encouraging him to talk, "they gave me a brief rundown, but I want to hear it from you." She wasn't going to play into his fantasy by calling him "sir."

He hadn't had her call him "sir" in years.

"I'm diagonally parked in a parallel universe."

Sam laughed, her voice sparkling through the room in a way that made Jack's chest hurt. "Look, you're the expert on this kind of thing. I'm just a former pilot and soldier who spends his days pushing paper and risking everybody's life except my own. Until four weeks ago."

"And what happened then?"

"I came from a routine evaluation of the Alpha Site on P2X-645…"

"What's that?"

"The Alpha site?"

"No, no- I know what that is. Those numbers."

Jack looked at her directly. "It's a planet. We travel by wormholes to get there." He paused. "We've been to hundreds."

Sam looked at him without any expression at all.

"This is the part where you tell me I'm nuts," Jack reminded her.

"No, this is the part where I'm jealous beyond belief because I've never even left Earth orbit." Sam smiled. "I wish you were right."

"I am, Carter."

She nodded. "Look, I believe it's theoretically possible. When they called me about you I started thinking…"

"Uh oh." Jack couldn't help himself.

Sam tilted her head. There it was again- the warm, almost fond tone to his voice that didn't fit at all with the circumstances. She shook it off and went on, "…and reading the newest literature, and maybe it can happen. But why you? Where'd you come from?"

"Another timeline, or reality, or something." Jack shrugged. "I can't tell yet."

"I'm supposed to believe you were in wormhole travel and alternate realities all in the same day?" Talk about delusions of grandeur.

Jack shrugged. "You're the brains. You always explained it to me."

"Me?"

Jack nodded. "You made the stargate work, Carter. You've been to dozens of those worlds, most of them with me."

"You?"

"Yeah. You were a captain and then a major on my team. You became a colonel after I was promoted. You saved my ass more times than I can count."

"I did?" The thought of leaving her nice, tidy lab and spacecraft with all their lovely doohickeys seemed anathema to Sam. The thought of saving his ass did have its attractions, however.

Jack didn't know how much to tell her. He didn't want her to freak out, though somehow he knew she could handle almost anything. Almost. "Your Dad's name is Jacob, your brother's name is Mark. Jacob died…eight years ago. You've always wanted to be an astronaut."

"That's all public knowledge."

"You like Jell-O- especially blue Jell-O. You bite your lip when you're nervous. You're great shot. That's not public knowledge."

Sam just stared at him. "How do you know this?" Her voice was nearly a whisper. She also noticed that he'd never looked at the gun the entire time she'd had it out. Not once.

"I know you." Jack suddenly saw an image illuminated as if by lightning- of her head tossed back, his arms around her waist, the sound of a weapon rattling to the floor but the memory flashed out just before Jack could remember if he pushed up her shirt looking for an entrance wound or to press his mouth to her skin.

Shit. Jack knew post-traumatic stress disorder when he saw it. - feltit. He couldn't breath again until she spoke.

"Would you like something to drink? I think I really need one." Sam rose, taking the gun with her. She turned around when he didn't answer. "Hey- O'Neill."

Jack's practiced look of casual interest slipped across his face like it had a thousand times before. "None of that weak crap. Diet coke's okay."

She stood in the kitchen and stared at him. "You know what I like to drink?"

Damn. Think. "Well, I was your CO for eight years, Carter."

Sam sighed and got out a coke for him and Coors for her, handed it to him and sat down. Jack noticed the gun stayed in the kitchen. "Eight years. Did we get along?"

He nodded. At that point he was almost afraid to elaborate, waiting for another image to come crashing into his unsuspecting mind. "You helped develop the hyperdrive systems for our faster-than-light ships, too."

Sam didn't know what to believe. Everything he said made perfect sense and no sense at all, and the way he talked to her was just- odd. As if he'd known her for years. Stranger still, that feeling didn't bother her in the least.

"Come on, Carter, it's all theoretically possible. Isn't it?"

"In theory, theory and practice are the same. In practice, they aren't."

"I know. That's why I'm stuck here. I've seen plenty of theories go bad, even yours." Jack smiled, "But I never saw anything you couldn't fix."

Sam rubbed her eyes. "I need to think about this. Where are you staying?"

"The Crowne Plaza."

"Oh, well, the Broadmoor must have been full," Sam said sarcastically.

"Yeah. Your tax dollars at work," he smirked. "Hopefully I won't be here too long."

Sam briefly and inexplicably hoped he would. Then she got up and showed him to the door. "How about I meet you for lunch tomorrow? At the hotel, maybe noon?"

"I'll have to check my schedule." Jack said dryly. He let himself out, walked out to the street and got in his truck. Jack put his head back on the headrest and stared at the streetlights for a very long time, and then he finally started up the truck and drove off.

---------------------------------------------------------------------------

Jack wrote down another word and then checked his watch. 12:15. He sighed. It seemed like much of his life had been spent waiting for Sam Carter, in one way or another.

Give me a minute sir, just one more minute.

Carter!

Not yet sir… not yet…

Carter! I can see my house or can I be the hologram next time or can we blow this…

"Thanks for waiting," she said.

"What?" Jack startled.

Sam stood in front of him. "They faxed over more of your files to me, and it does make for fascinating reading."

"Fascinating wouldn't be the first word that comes to my mind."

"I suppose not." Sam looked down at him thoughtfully. "How are you feeling today?" He certainly looked fine, very fine, in fact. Blue jeans, black cotton sweater and white t-shirt, an amazing complement to his short silver hair. Sam found herself wondering again why she was attracted to the lunatic fringe. He stood and she thought he looked taller today- or maybe it was just that they were so close.

A fact that didn't bother either of them in the least.

Jack was touched that she would be concerned about how he was feeling, considering her she'd been leading a normal astronaut's life- now that's an oxymoron- until he met her. "Things are more like today than they've ever been before." He smiled a little and motioned with the newspaper. "How about the grill?"

"I was thinking more the café, it's got a better view."

"Nah. Too noisy."

"Are we going to have to arm wrestle over it?" Sam smiled, her arms crossed.

Jack looked at her in stunned silence. "Uh, the café it is, then." They walked over to the restaurant, and he motioned her in. "Ladies first," he said quietly.

"Are you all right?" Sam asked as they were seated by the window.

Jack looked out at the street. From what he could see, this version of Colorado Springs was the same as his own. "Yeah, I'm fine. You- I- just remembered something, that's all." Jack turned to look at her. Except for the faint scar on her left forehead that was missing, they were identical. Right down to the way she incessantly tapped his pencil on the table. Without thinking, he took the pencil back in a manner Sam felt was altogether too familiar.

Jack toyed with it absentmindedly. "Do you ever wonder why, if everyone uses #2 pencils, they aren't #1 by now?"

"The thought never crossed my mind."

"It's probably the only thought that hasn't, Carter."

"Call me Sam, please. This is hardly official business."

He didn't want to call her Sam. That name was taken. "All right, Sam it is."

Sam watched him look back out the window, almost as if he didn't want to look at her. Yesterday he'd seemed so concerned that she believe him- and she still wasn't sure she did- that he was animated, even upbeat- but not today. Sam decided that even if O'Neill was nuts, he needed a friend, and if he wasn't, he needed one even more. "Since you know all about me, how about telling me about yourself?"

"Don't you already know everything?"

"I doubt you told the Air Force everything, Jack. Tell me something that doesn't have to do with- the- program."

He noticed the hesitation in her voice. "Still don't believe me?"

"Everything you told me is theoretically possible, but I need more details, Jack- as much as you can remember."

He shook his head. "You don't get it, Sam. I'm so dense light bends around me."

"Obviously, Jack, you just play dumb. And you're still avoiding my question."

Fortunately, the waiter temporarily rescued Jack, and they ordered. Unfortunately, Sam had an air of infinite patience about her. He sighed in surrender. "Well, I like to fish. I have a cabin in Minnesota that's on this great little pond, and…" a sudden look of alarm crossed his face. "God. I don't have it anymore, do I? I wonder if Sara still does."

"We could find out, Jack." Sam said, concerned. Her plan to cheer him up had backfired impressively.

"No, don't." He looked at Sam with a pained expression. "I can't go up there again. I probably can't even visit Charlie's grave, can I?"

"No, because you're buried right next to him." Sam said quietly. "I had to see for myself. In fact, I'm not sure you should even be in this city."

"What a goddamn mess, Sam." He turned to stare out the window again.

"Jack, what are you going to do about her?"

"What do you mean?" His head snapped back.

She looked at the ring on his finger. "Aren't you still married?"

It took Jack a few seconds to figure out what was happening. "No, not her." You.

"Oh. I'm sorry."

"What?" In his wildest dreams Jack could not imagine a more surreal conversation. He'd think it was fucking hilarious if it wasn't actually happening.

"You've been dead for over a decade, here. She can't possibly know you, wherever she is."

Jack stared at her. "No, I'm sure she can't."

Normally a compassionate person, Sam was nevertheless alarmed by the fact that she felt so utterly compelled to do something to set Jack's mind at ease. Without thinking, she touched his hand. "Can I help, Jack?"

He blacked out and there was nothing but the touch of her cool hand in the searing blue heat and God, the pain. Jack couldn't see anything, couldn't hear anything, he could only feel the heat, the pain that pinned him to the wall, and her hand. He was dying, he knew. But she was there.

The feeling washed over him and left Jack shuddering as he dropped his gaze to her hand. He met Sam's eyes with a look that stole her breath from the pain and longing contained in it- so intense it seemed to have forced its way out through a fissure in his soul; and then it was gone. But not before Sam got the clear feeling that she wasn't the recipient of that look so much as the cause of it, and she couldn't figure out what it was that she'd done wrong.

The waiter brought their drinks and Jack picked up his beer as if the previous few minutes had never happened. "Guess I'm the one who needs the beer, today," he toasted her.

"Well, if I'm going to help you, you can't expect me to drink and derive." Sam said, trying to salvage the conversation.

Jack put his beer down with a smile. "Great. Bad math jokes. You know I don't get those."

"No, I don't know that."

He sighed. "Sorry, Sam. I wish we could start this conversation over." He motioned the waiter over for another beer. "But I guess it's all just water under the dam, now."

Sam wondered if he was ever serious, but decided now was not the time to ask as the waiter arrived. She eyed Jack's steak with amusement. "Lunch?"

"Hey," he said, poking his fork at her, "I'm not at the top of the food chain just so I can be a vegetarian." He sawed off a chunk. "One night, you- your other self- ate four of these."

"I did?" Sam didn't quite believe that one.

"Yeah. We needed the energy because we had these idiot magic alien devices that…" Jack stopped cold and looked at her. "We almost died."

"It sounds like that happened a lot, Jack."

"This was different." He didn't say anything more and Sam didn't ask. She was left with the unsettling feeling that her memory had a ten-year gap in it that she'd never be able to fill.

After dinner Jack finished off his fifth beer. "I think you've had too much," Sam nodded at the empty glass and then stood up, offering her hand. "Come on, let's get you up to your room. We're not going to get any work done today."

"I can take care of myself, Sam." Jack got up. "You've done enough." Sam hesitated, trying to read sarcasm into his words, and decided to give him the benefit of the doubt. "Sorry, I read the other Jack's records, too." She put her hand on his arm and guided him out of the café and up to his room, and waited as he tried to get the door open.

"Are you going to be all right?"

"I'm laying even odds." He straightened up looked at her with such affection that it would have melted her heart had she known the context of it- but as it was, it just disturbed her. "Samantha. God, I missed you," he whispered as he wrapped his arms around her in a sudden embrace.

Sam didn't move or even breathe as he held her. After several moments, he lifted his head and touched her face gently, then turned and disappeared into his room. Sam stood there wondering what the hell had just happened.