A/N: Thank you so much for your great feedback on the last chapter! I couldn't have Addison and Derek go back to New York without having Archer making an appearance. And I'm glad to know that people like Archer as much as I do. There's lots of Archer in this chapter; I hope you like it. And as always, thanks so much for reading and reviewing! Stay safe and well, and have a great last weekend in August!

"Archer, what are you doing here?" Addison demands.

She and Derek are sitting in the living room with a now fully-clothed Archer and a woman who's name they still don't know. (Quite honestly, Addison has her doubts about whether Archer knows the woman's name).

"Archer," Addison prods when her brother doesn't answer. "What are you doing here?"

"What does it look like I'm doing here?" Archer gestures smugly to the woman sitting next to him.

"I guess I walked into that one," Addison mutters to herself. She turns to Archer's flavor of the week and does her best to offer a sincere smile. "I'm Addison. Archer's sister."

"Oh," the woman smiles widely. "It's nice to meet you. I'm Kandi."

Addison glances at her brother and raises an eyebrow. Kandi? Bizzy wouldn't be impressed. But then again, maybe that's part of the appeal.

"So, do you have a house out here too?" Kandi asks Addison.

"This is our house," Derek says flatly.

"Oh," Kandi blushes brightly.

But Archer remains unruffled. "Actually, this is my sister's house. Henry David Thoreau over here left it to her in their divorce," he continues, gesturing toward Derek. "All so he could go out in the woods and be one with nature and all that." He turns to his sister. "What are you doing here anyway?"

"We're here for—" Derek begins, but Archer cuts him off.

"I don't care what you're doing here, Shepherd. You divorced my sister. I don' t have to pretend to be nice to you anymore."

Derek blinks in surprise. "When did you ever pretend to be nice to me, Archer?"

"So, I'm not a great actor," Archer shrugs, turning his attention back to his sister. "What are you doing here?"

"We're here for Weiss' birthday."

"We?" Archer raises an eyebrow.

Addison feels her cheeks flush at that. "Well, I'm here," she begins primly. "And Derek's here ... separately. We're both friends with Weiss."

"Weiss ..." Archer looks thoughtful. "He's the one who's married to the blonde?"

"Savvy. Yes," Addison nods.

"And she's here too?" Archer asks hopefully.

"Of course. She's his wife."

"So, they're still married?"

"They're still married," Addison nods.

"Happily?"

"Archer."

"What?" Archer shrugs. "I was just asking."

"They're very happily married," Addison says tightly.

"No one's happily married," Archer scoffs.

"They are. And even if they weren't, you have a ... uh ..." Addison trails off, cocking her head towards her brother's latest conquest.

She's not sure how to complete that sentence. A girlfriend? That's likely not the case. A friend? That's insulting. A Kandi? That's more insulting.

In any case, it's not like it really matters when it comes to Archer. Having a girlfriend or a friend or a Kandi isn't going to stop him from sleeping with other people's wives. But then again, she's not exactly in a position to judge.

"I remember liking Weiss," Archer says fondly. "Let me know what you're all doing tonight. Maybe I'll meet up with you."

Derek clears his throat audibly. He doesn't have to say a word for Addison to know what he's thinking. How very presumptuous of Archer to invite himself somewhere he was never invited in the first place.

In all honesty, Addison wouldn't mind it if her brother joined them. Archer's her family and she's missed him. But she knows Derek would hate it ... which shouldn't matter because he's her ex-husband. But if the past twenty-four hours have taught her anything it's that things with her and Derek aren't that simple.

"So, wait ..." Archer trails off in confusion. "If you're both here for Weiss' birthday, why aren't you with him? Why did you come back here?"

"We needed somewhere quiet to talk," Addison says primly.

"Talk?" Archer raises an eyebrow. "Montgomerys don't do that."

"We do that," Derek insists. "This weekend, we've done that a lot."

"We?" Archer folds his arms across his chest, unimpressed. "You're not a Montgomery."

Derek is tempted to tell Archer that there's a man named Robert (that they met on the beach and whose wife and baby they helped save) who firmly believes he's a Montgomery. But he knows that won't go over well with his former brother-in-law, so he doesn't push it.

"Addison and I talk," Derek amends.

"How nice for you," Archer says giving Derek a saccharine smile. He turns to his sister, his expression serious. "You're not going to kick me out of your house, are you?"

Addison exchanges a look with Derek and she shrugs helplessly. She's never been good at saying no to her brother; Derek knows that about her.

"Of course I'm not going to kick you out of my house," she tell Archer. "You can stay here. Just have the cleaning service come when you leave. And ..." she shudders, "make sure they change the sheets in the master bedroom."

"Don't worry," Archer waves a hand dismissively. "It'll be taken care of."

Addison doesn't doubt that. What she's less confident about is whether it'll be taken care of because Archer calls the cleaning service. The more likely option is that she'll make the call when she gets back to LA.

"We should have a drink," Archer says, clapping his hands together.

Addison shakes her head. "We just got back from a winery. And we're going to be drinking later tonight."

"Yeah, so?" Archer shrugs.

"So, we're going to stick to water," Addison says.

"We?" Archer looks at his sister disapprovingly.

"Yes," Derek nods. "Addison and I."

Archer shakes his head discontentedly. "Suit yourselves." He gestures to himself and Kandi. "We'll have a drink. You two can have water. But at least make it sparkling."

"Fine," Addison chuckles.

"Good," Archer grins. "Derek, why don't you help me get the drinks?"

"Me?" Derek looks at his former brother-in-law in surprise.

"This is your place," Archer points out with exaggerated politeness. "The least you could do is be a good host."

"But you just said—"

"I know what I said, Shepherd," Archer cuts in. "Just do me a favor and come help me."

Derek looks at Addison warily, and she shrugs in response.

"Fine," Derek mutters, shooting Archer an unimpressed look. "But I'm not doing it for you."

"Who are you doing it for then?" Archer challenges.

"Well, I ... " Derek trails off.

He's not ready to answer that. And he's especially not ready to answer that in front of his former brother-in-law.

"It doesn't matter," he recovers. "Come on, Archer. I'll show you where we keep the good stuff."

"Oh, I already know," Archer chuckles as they move toward the kitchen together. "Not my first trip to Chez Montgomery."

"Of course," Derek says tightly as he stands up from the couch. "You lead the way."

xxxxx

"They've been gone a long time." Savvy glances down at her watch and frowns. "I hope they're okay."

"I'm sure they're fine," Weiss reassures. "I'm sure they're just—"

But he cuts himself off when Nancy and John join them in the living room. Nancy no longer looks tipsy, and John, who'd been fine the whole time, looks about the same.

"Look who finally woke up," Weiss grins.

"How was the beach?" John asks.

"Nice," Savvy smiles. "Quiet."

"Where are Derek and Addie?" Nancy asks in confusion as she and John join Savvy and Weiss on the couch. "Still out there?"

"No," Savvy shakes her head. "Addison said they were going back to their place out here. She said there were some things they needed to take care of there."

"You don't think they're dividing up their things, do you?" Nancy asks, her eyes wide.

"No," Savvy and Weiss insist firmly.

They turn to each other and smile.

"That's just not the impression I got," Savvy explains more calmly.

"They better not be dividing up their things," Weiss mutters under his breath. "Not if they know what's good for them."

"They're not dividing up their things," Savvy insists ... hoping that if she says it confidently enough it'll somehow make it true.

"They seemed to be on good terms at the Vineyard," Nancy agrees. "And in the limo on the ride back." She runs a hand through her short hair. "But then again, things between them seemed pretty tense at brunch." She shakes her head. "One second they're hot, the next they're cold."

"One second they're here with us, the next they're off somewhere by the themselves," John chimes in.

"That's a good thing, though," Nancy smiles.

Savvy nods in agreement. "They need time to talk. And they need time to talk on neutral ground. And while Seattle may have ... a lot going for it, it's anything but neutral."

"Honey, Derek's not here," Weiss scoffs. "You don't have to pretend to like Seattle. Let's face it, the only good thing Seattle had going for it was Addison. And she left."

"Derek's in Seattle," Savvy points out.

"No, McDreamy's in Seattle," Weiss disagrees.

The others nod in concession. They can't exactly argue with Weiss on that.

"I'm just glad that Derek's with us this weekend," Savvy says optimistically.

"Me too," Nancy smiles. "And he might not admit it because he's very stubborn, but I know my brother, and I know he's but glad he's here too."

xxxxx

For the first time all weekend, he wishes he were back in Seattle. Well, maybe not in Seattle, but anywhere besides where he is right now—in the kitchen of his place in the Hamptons, alone with Archer Montgomery.

Technically, it's Addison's place in the Hamptons. And technically, Addison is just a couple of rooms away, but still ... the whole situation feels suffocating.

"Shepherd, are you planning to make me a drink sometime today?"

Derek looks up in surprise. Clearly, he misunderstood his former brother-in-law. When Archer invited him to the kitchen to help make drinks, what he was actually doing was inviting him in there to make all the drinks.

He should have expected that. But, in all honesty, he was caught off guard. Maybe he's been away too long.

"Shepherd," Archer taps his foot impatiently. "Those drinks aren't going to make themselves."

"Right," Derek mutters, twisting open a bottle of gin and pouring some into a tumbler.

"You realize I'm not your twelve-year-old girlfriend," Archer mutters, gesturing to the glass.

"Excuse me?"

"I'm an adult, Shepherd. Pour me an adult amount of alcohol."

Derek's not sure he agrees that Addison's brother is an adult. But he knows if he tells him that, Archer will tell him exactly what he thinks of him. So, he keeps quiet and pours his former brother-in-law more gin.

"Better," Archer approves as Derek puts the cap back on the gin.

"I'm so glad," Derek says with exaggerated politeness.

"I'd watch the tone if I were you," Archer warns.

"Excuse me?"

"You heard me, Shepherd. After the way you treated my sister, you're lucky that I'm speaking to you at all."

Derek blinks in disbelief. "After the way I treated Addison? Archer, I don't know which version of the story you heard, but she—"

"Cheated first," Archer shrugs. "Yeah, so?" He looks at Derek squarely. "Maybe that stuff means something to some people. But not to me."

"Of course it doesn't mean anything to you," Derek says irritably. "Considering your track record with married women. Women in general, actually."

"Don't act like you're better than me," Archer snaps, his eyes flashing angrily. "I may sleep around, but I've never once tricked a woman into uprooting her entire life for me."

"What?"

"She had a life here. She had a career. She had friends. And she had me. And she gave it all up for you. She gave up everything for you, and you never had any intention of trying to make things work with her."

"You don't know that. I did try."

"How? By ignoring her? By sleeping with someone else?"

"She told you that?"

Archer shrugs nonchalantly. "Even if she hadn't, the medical community is smaller than you'd think." He gives Derek a haughty smile. "You wouldn't believe the things we're saying about you."

Derek feels his body stiffen. At Seattle Grace, he's a Rockstar. At Seattle Grace, he's McDreamy. He never bothered to consider the larger medical community. He wants to say he doesn't care what the larger medical community thinks about him, but the truth is he does.

He knows Archer's trying to provoke him with that taunting smile and his haughty comments about the larger medical community. The thing is, it's working.

Because he can imagine what the medical community is saying. They're probably saying the very same things he used to say and think about male attendings who slept with interns. The-male-attending-who-sleeps-with-an-intern club is not a club he ever wanted to belong to ... but he's different than all those other male attendings.

He needs to tell Archer as much.

"The medical community doesn't know the whole story."

"But I do," Archer shrugs. He looks at Derek squarely. "Why'd you do it? Was it revenge? Why'd you lead her on if you had no plans of taking her back?"

"I didn't do that."

"You did, Shepherd," Archer seethes. "And now she's in LA ... working at a private practice. You destroyed her career. And not just her career. You realize that, don't you? And you didn't just hurt her. You hurt a lot of people. You hurt her and you hurt me and you hurt—"

But he cuts himself off when he sees Derek take a large gulp of the gin and tonic that's sitting on the counter.

"Hey! That was supposed to be my drink," Archer sputters. "What the hell are you doing?"

"I ..." Derek swallows roughly.

He knows exactly why he's drinking what was supposed to be Archer's gin and tonic. But he wouldn't know how to even begin to explain it.

So he busies himself by taking another large gulp.

"Hey, take it easy," Archer rebukes, eyeing him critically. "Slow down. You're spending a lazy Saturday in the Hamptons, not a night at the frat house with the twelve-year-olds in your fan club."

"Funny," Derek mutters.

Except it isn't. None of it is.

He had absolutely zero intentions of drinking that afternoon. But then Archer started talking—and belittling him in that obnoxious way that Archer seems to have down to a science. And it was obnoxious ... at first. Until it wasn't. Until it started to ring true. Too true.

Archer's an unfaithful ass with no morals, who's led on more than his fair share of women. But he's never led a woman on so much that she uprooted her life for him.

Derek has.

The cynic in Derek rationalizes that Archer has never been with a woman long enough to do something like that. But the less cynical side of him wonders if maybe that's a line that even Archer Montgomery wouldn't cross.

Hence, the drink.

He knows he's not blameless in the breakdown of his marriage. He's acknowledged that time and time again this weekend.

But something about Archer's accusations are striking differently. Something about Archer's accusations are cutting deep.

And unlike Addison and Nancy and even Weiss, to an extent, Archer doesn't see both sides. Archer refuses to see both sides.

And Archer isn't going to ease up on him. Archer has no problem going in for the kill.

And he can't take that. Not right now.

"I have to get out here," he announces, bolting from the kitchen.

"What?" Archer demands, quickening his pace to keep up with Derek.

"I have to get out of here," Derek repeats as he darts into the living room.

"Derek," Addison quickly pushes herself up off the couch and looks at him in surprise.

But Derek doesn't meet her eyes. Right now, he needs to think, and he needs to be alone. He needs to get out of there.

So he makes a beeline for the door, and wordlessly lets himself outside.

"Hey!" he hears Archer scream as he forcefully closes the door behind him. "You owe me a drink!"