Hi! This is a Maddison fanfic – hence, I don't recommend reading this to people who don't like Mark or Addison. I'm English, so I'm not fluent in American (that being said, I like to think I know the basics, because I get pretty annoyed when somebody writes a Grey's Anatomy fic and writes 'Mummy' instead of 'Mommy', and vice versa with Harry Potter fics).

Main ships appearing in the fic (beyond Maddison) will be MerDer, Lexzie, and Bang (others, too, but ones I can't mention without creating spoilers). Having mentioned that, I'm inclined to add that I'm not a very nice person, and not all of those couples will celebrate happy endings.

Sorry for the length of that. Anyway, enjoy!

Disclaimer: if I owned Grey's Anatomy, Addison would still be a member of the main cast.

Chapter 1: Separator

Stepping inside his wife's Massachusetts apartment, Mark Sloan was immediately struck by the thought that something was wrong.

For one, there was the fact that it was completely dark throughout the apartment; this was definitely a strange occurrence, because Lexie – despite the supposedly amazing photographic memory which kept her grades so high – was constantly forgetting to turn off the lights in her apartment. Mark knew better than anyone because he was the one paying the electricity bills.

And then there were the obvious factors. The heavy aroma of scented candles hung in the air, stifling, and further inside, somebody moaning loudly – he, being an expert in sex, instantly recognised the type of moan it was. In the corner of the corridor, where Lexie's usual pile of abandoned sneakers and trainers lay, there was also a well-polished pair of men's leather shoes. Alessandro Berluti, fancy. Definitely not Mark's – two sizes too small.

Feeling like a character in a horror movie, Mark stepped further into the apartment, in the direction of the bedroom door, which was the only closed door. He heard the faint sound of creaking bed springs, and vaguely remembered telling Lexie to remind him to have them fixed when he'd visited last weekend.

Mark stayed with Lexie every weekend. It was a compromise, as Lexie lived in Columbia, and Mark in Manhattan – they were married, but Lexie wasn't going to give up Harvard (who would?) and Mark refused to leave the practice he'd spent so many years working on. Today wasn't during the weekend, it was Thursday.

He'd left earlier than usual, for the sole purpose of surprising Lexie with a romantic get-away for their third anniversary. Because they'd been so distant lately, and it felt too much like the relationship Mark's parents had shared for him to be comfortable.

It was their anniversary. The third one.

That thought was the one which pushed Mark to slam open the door, revealing his wife and best friend in the throws.

That was his bed. He paid for it. He slept in it. And those sheets? The Italian paisley, the ones he also paid for? Those were his favourite sheets.

He glared at the two, frozen in place, Lexie still sat atop Sam, the two of them completely naked.

"Classy," Mark told them, his voice stony. He chuckled coldly, feeling some of that cruelty he'd felt watching his mother convulse on the floor as a child – overdosing, again – and later watching his father, dry-eyed, as the man who raised him was taken off life-support. "I mean," he continued, "who knew the two of you could have such an affinity for clichés?"

"Mark," Lexie started to speak, her voice shaky and face pale, crawling off Sam, hugging a sheet to her chest.

"Really, Lexie?" he asked her before she could continue. "What's with the sheet? No need to be modest. After all, we've both seen you naked here."

She flinched.

"Mark, look-" Sam too started to say, but he was also intercepted before he could finish.

"Hey, though," Mark said. "At least we don't have kids, eh Lexie? Sam, what's gonna happen to your Maya? I don't think she'd be pleased to hear her Daddy was whoring around with some Other Woman."

"Mark!" Lexie exclaimed. "Mark! Don't! I just-"

"You just what, Lexie?" he asked, voice harsh. "What, did he fall inside you? I don't see any guns and, from what I saw, it was you who was on top."

He pushed open the closet doors and began to pile clothes into his arms.

"Mark?" Lexie asked, panicking, and pushing herself up off the floor, forgetting all about the sheet and her modesty. "Mark? Mark? What are you doing? Mark?"

"Oh, don't worry," he told her icily. "You can keep your stuff. I'm just collecting my things, and then I'll leave the two of you to whatever you were doing before. I'll mail you the divorce papers."

"Mark! Mark, I'm sorry!" she yelled, clutching at his shoulder. "Mark, stay! We can get through this – we can, we're MarkandLexie – but you have to stay, or else, or else we won't be able to!"

He shook off her clammy hands. "Save it, Lex," he told her, voice finally softening, if only in the slightest. "I was a manwhore before I met you, you know that. I stayed for you, I tried for you. I didn't wanna be my father. I loved you. I did it, Lexie – if I can do it, so could you have. And at least I got my wish, because it's not my father I am now; it my mother. Fuck you."

She stayed perfectly still as he left, her mouth open slightly.

The door slammed shut behind him.

"Loved?" she murmured, a shell-shocked expression on her face as she slumped down onto the bed, his words forever reverberating inside her head.

Weary after a long seven and a half hours, Mark sat down at the bar vowing to never fly economy again. The bar was dimly-lit and over a decade had passed, but he still recognised the man he'd once considered as good as his brother.

"Scotch on the rocks," he told the bartender, waiting for Derek to notice him.

It didn't take long; Derek swung around to face him as soon as he heard the familiar voice, his face breaking into a smile. Apparently, he too had found it easier than it would have been expected to recognise a man he hadn't seen for long.

"Mark Sloan!" he exclaimed, hugging him.

"Derek Shepherd," Mark grinned. "You've gotten old."

"And yet you haven't aged a day," Derek replied, in good humour. "Except… is that a nose job?"

"I slept with Celia Kim and her husband found out. He throws pretty good punches for a puny little businessman."

Derek laughed. "You haven't changed at all," he said, and Mark downed some of his scotch to stop himself from feeling any hurt at the comment (after all, had he really changed?) and refrain from talking about matters he'd rather not be talking about.

"Speaking of changes," he said, "congrats on your wedding. Two more days of freedom, right?" He gave Derek a pat on the back.

"Yeah," Derek smiled nervously. "I was meant to be having my bachelor party right now, but it was men-only, which meant I had a pretty small pool of volunteers. Rose's brother got food poisoning and Burke – he's a cardiothoracic surgeon at the hospital – got paged ten minutes in."

"What about Weiss? I thought you and he stayed friends when you were the only ones left at Columbia."

"We are. He and Savvy are currently in Slovenia completing the adoption process on their kid, Andres. He's four. Cute. They were meant to be back in time, but there was some kind of complication and now they're staying longer."

Mark frowned. "How come they're adopting?" he asked.

"Savvy's mom got breast cancer," Derek explained.

"Was Savvy's mom supposed to carry their baby?"

"Most of the women in her family have had it by now. When she heard, Savvy got tested for the gene, the test was positive, she freaked out and had her breasts and whole reproductive system removed."

"That's terrible. How is she? How'd Weiss take it?"

He'd only known Savvy briefly, back when she and Weiss were still dating. She was a sarcastic blonde, from what he remembered, and best friends with Nancy, one of Derek's four sisters. She'd been studying law.

"They're doing okay," said Derek. 'They're about to begin nipple reconstruction, nearing the end of the process, you know?"

"Well, I do specialise in breasts," Mark smirked. "But hey, let's not dwell on sad topics – why don't I make sure this is the best night of your life?"

He woke up naked on somebody's floor, a slight breeze blowing in his direction from a nearby fireplace. The blonde from last night was standing over him awkwardly, wrapped in a robe.

"This is…" she murmured, "humiliating on so many levels."

Mark winked at her, seemingly unashamed of his nakedness – because hey, did he really have anything to be ashamed of?

"You have to go," she told him firmly.

"Come back down here," he proposed, "we'll continue right back where we left off…"

"You have to go," she repeated. "I'm late. Which isn't what you want to be on your first day." She tossed him his clothes. He sniffed them and shrugged; no point changing. They didn't smell too bad and anyway, he'd be changing into scrubs once he got to work.

"I'm Mark," he introduced himself once he was decent, holding out a hand for her to shake. "I start my job today too. Where d'you work?"

"Meredith," she offered. "I'm an intern at…" she started but trailed off. "You know what?" she said. "We don't have to do the thing."

"Oh, we can do anything you want."

"The Thing," she told him. "Exchange the personal details of our lives, pretend to care… look, I'm going upstairs to shower. And you won't be here when I get back."

He glanced out the window, which didn't have any curtains. The thought that anybody could have seen him naked or in the throws crossed his mind, but he didn't particularly care. What he did care about was the shiny, new Mercedes he'd rented, which wasn't parked out front, or anywhere in sight for that matter.

"Hey, where's my car?" he yelled after her.

"Joe took your keys after you did all those shots!" she called back.

"Who's Joe?"

"The bartender! At the Emerald City Bar! From last night!"

"You're on first name terms with the bartender?"

No answer.

Grumbling to himself, Mark exited the house and pulled out his mobile to look for directions. He didn't have the time to actually take a look at them, because he found himself falling backwards as he crashed into someone.

He managed to steady himself before he could fall, but she wasn't so lucky.

"Damn it," she swore, ignoring Mark's offered hand and pushing herself up off the floor and brushing invisible dirt off a (tightly-fitted) dress.

He apologised , handing her the files she'd dropped.

"It's okay," she replied, before glancing at her watch. "Crap," she murmured, rushing toward a beat-up Chevy parked nearby.

"That your car?" he asked her. "Doesn't look very you."

"It's my roommate's," she told him. "We carpooled yesterday in my car, and I left it at the hospital so she and my other roommate would have a way of getting back."

"How'd you get back?" he asked her curiously.

"I took a cab," she explained. "Probably the better choice, seeing as I'd been drinking anyway. Not," she added hastily, "that I'm a drunk or anything. It was just a bad day."

She glanced again at her watch. "I really have to go," she told him apologetically. "Work emergency."

She drove away, and he cursed himself for not asking directions to Joe's, because he sucked at map-reading.

It was rude of her, to be so distracting with her red hair and pretty face that he couldn't think clearly.