He's not sure which kills him more: the not knowing or the waiting.

At first, he paced the halls. After a while, he gave up and sat by the elevator bay like a lost puppy. Now he's hiding out in the attendings' lounge. He doesn't want to have to face Addison or Richard.

Part of him wishes Tucker's surgery would have taken longer or that he would have been admitted later, so that Derek would still be up in the OR. Being near her, knowing that he was in as much danger as she was, that would help. Having something to do would make the waiting bearable, but sitting here, doing nothing, just waiting, it kills him. He's a surgeon. He's used to being in command, used to walking into the OR knowing that he can cure the patient on the table. He's not used to feeling so helpless. He's not used to spending hours in the hospital with nothing to do. Truth is, Derek Shepherd doesn't know how to not be needed.

Despite everything that has happened between them, Derek wishes Mark was here. He'd know how to alleviate all this tension and worry; he'd be able to get Derek to loosen up and maybe not be obsessing about what could possibly happen to Meredith for five minutes. With Mark being so forcibly cut out of his life and Meredith not really speaking to him, there was nobody left for him to confide in. He and Burke were more like amiable co-workers than friends, and he and Richard…well that relationship was more professional than anything else.

The door opens, and Derek starts, having completely forgotten that there are other attendings at the hospital that make use of the lounge. Part of him hopes that it will be Burke, saying that everything is over, that it's all fine, and another part hopes that it will be Addison, so that he'll at least have the company of someone who knows him, but it's neither: it's Nelson, the other attending neurosurgeon.

Nelson crosses the room with an amiable smile and helps himself to a water bottle from the fridge. "How'd your surgery go?"

"Good," Derek replies quietly.

"Quite a day we're having, huh Shepherd?" Nelson chuckles to himself.

"Yeah." Derek wants to laugh with him at the absurdity of it all.

"Could be our last day on Earth, you know? I would have thought you and Dr Shepherd would have been using all this time to get...reacquainted." He grins suggestively.

"Dr Montgomery is with a patient," Derek replies curtly. He hates it when people refer to Addison as Dr Shepherd. He's Dr Shepherd.

"Oh. So she's the one helping Miranda Bailey."

"Yes." There's an awkward silence. "Well, look after yourself Shep," Nelson says before heading out of the lounge.

Derek sits in his chair for a moment, seething. Shep. What does Nelson think he is, some kind of dog? He's Derek Shepherd, the world-renowned neurosurgeon for Christ's sake!

This is the kind of thing he and Mark would have laughed at. Mark would find it all hilarious, especially the bit about Addison. Hell, he'd probably be imagining it. Not that he needed to use his imagination.

The whole thing with Mark begged the question: why did Addison come back? Why didn't she stay in New York with Mark and her practice and all her friends? He isn't sure he buys this whole "I think you're the love of my life" story, and if that was true, why did she wait so long to come and find him? Why hadn't she come running right away, before he'd gotten involved with Meredith? He wishes she'd stayed in New York. He'd be so much happier if she'd just left him be. Since she's come back, everything has been more complicated, and a good night's sleep is a rarity. So is sex. Come to think of it, he hasn't been happy, truly happy, since that last morning with Meredith…

Derek stretched out in bed. The sun was filtering through the partly closed blinds, casting tiger stripes of light over the room. He could hear the sounds of George and Izzie downstairs making breakfast, even though their alarms shouldn't have gone off yet. Maybe they were hoping to get out early, before he and Meredith got up, which was not something he'd complain about.

Meredith was still asleep beside him. She slept with abadon, peaceaful and unencumbered. There were no complications in her life, no messiness. She was so lucky.

He caught sight of his phone lying on the bedside table, and thought fleetingly of Addison and all her calls, which he'd been ignoring. He wondered briefly what this could mean, but dismissed it as Meredith began to stir beside him. It was nothing. If he didn't answer, she'd stop calling.

"Morning sleepyhead." He rolled over so that he was facing her, and propped hi head up on his fist.

Meredith smiled that crumpled, sleepy smile of almost 5:30 A.M. "You're up early," she mumbled.

He chuckled. "So are you."

Surprised, she rolled over to face him, now slightly more alert. "What time is it?"

"Twenty-five after five. You could have had another five minutes." A slow wistful smilke crept across her face. "But since you're up…" Grinning, he rolled on top of her, knowing there was no need to finish his sentence.

Meredith smiled as he began to kss her cheek, her nose, her neck, slowly creeping down, down, pushing aside the collar of that sexy little Dartmouth shirt she always wore even though it was starting to get a little ratty. She let herself be indulged for a moment, before pushing gently on Derek's chest in a half-hearted attempt to get him off. He smiled as ked kissed her collarbone, and round to the other side of her neck. He would win this morning, he always did. In Meredith's world, sex trumped obligation.

"I need to go shower," Meredith protested, laughing, as Derek's lips brushed her jaw line.

"Mmm," Derek agreed with mock seriousness. "You have time. Lots and lots of time," he mumbled into her neck, slipping his hands up underneath her shirt.

"Seriously!" Meredith giggled, pushing at his shoulders.

"I'm being serious." Derek's hands plucked at the waistband of her legging. "I'm very serious."

"No you're—" He silenced her with a kiss: long, steamy and full of desire. He'd definitely win this one.

The alarm sounded shrilly; their habitual 5:30 wake-up call. With one last groan of effort, Meredith sat up and pushed Derek off. "Five minutes are up," she announced. "Now I really need to go shower."

Derek groaned and collapsed back onto the bed. Meredith laughed as she leaned in and kissed him. "Can I join you?" He tried one more time.

"Don't you have an early surgery this morning?" Meredith asked as she disentangled herself from the blankets before getting out of bed.

"Damn." Derek glanced at the clock on the bedside table. 5:32. He had to be in the OR in a little less than two and a half hours. "I can skip pre-op. They don't actually need me until eight…"

Meredith laughed. "Nice try. Go have something to eat. Maybe if your surgery goes well we can celebrate." She winked, before heading off to the bathroom.

"You bet," Derek called after her. After this morning, he'd definitely be collecting.

He lay in bed for another five minutes, listening to the faint sounds of the shower coming from down the hall. He thought briefly about joining her, but resisted.

George and Izzie were gone—he'd heard the telltale slam of the front door a while ago—which meant that he and Meredith had the house to themselves. Just like when they'd first met. Derek chuckled as he remembered that first morning two months ago. Meredith's living room floor was actually quite comfortable. And her couch…

Knowing Meredith would be a while in the shower, Derek took a little bit more time going about his morning routine, but not too much time; there was still that surgery to consider. He was halfway through a bowl of muesli when Meredith returned, still wearing her pyjamas and smelling strongly of her conditioner: that beautiful floral scent that he couldn't name.

"You really should get going," Meredith chided. "You don't want to be late for your surgery."

Derek set down his spoon. "I have some time," he replied with a suggestive grin.

Meredith laughed and pretended to shoo him away. "Go. I'll see you at work." She leaned in and kissed him; it was short and quick, practiced, like they'd be doing it every morning for the rest of their lives. Derek wouldn't mind spending the rest of his life like that. With her.

"All right. I'm going," Derek got up from his chair, crossed to the front door, and pulled on his coat, ever mindful of the November chill. "But you can bet I'll be collecting."

Meredith's laughter followed him out of the house…

Derek fiddles with the band of his watch. They were so happy. He and Meredith were so happy, and now, they hardly speak to each other about anything not related to work, and that's only when they are working on something together. First Mark, now her, and he can't help but think that Addison is the common thread here. She slept with Mark; she showed up in Seattle and things with Meredith ended. Then again, he's also a common thread. If he hadn't worked so much, Addison wouldn't have had to sleep with Mark to fill the void left in his absence. If he hadn't ignored Addison's calls; if he'd thought more about divorce; if he'd been more honest with Meredith, maybe they would still be together.

Derek sighs. She has to make it She has to be okay. You can't feel so strongly about someone and not get to tell them how you feel.

The frustration is beginning to build again, so he stands up. She does not get to do this to him. She does not get to do this! Furious, he grabs the chair and throws it across the room. This cannot be happening. Derek rubs his face, all the anger draining out of him. He doesn't know what he'll do if she doesn't make it.

Sighing, he strides out of the room. He can't sit around anymore. He'll go check on Tucker and then see if Addison needs a hand.

Time passes strangely for Meredith. She's sure it's been hours since Mr Carlson was admitted and they discovered the bomb, but it doesn't feel like it. It's like time has simply stopped; she has absolutely no sense of it passing at all. Cristina has been gone a while now, so there is nobody to talk to. Young came back with the blueprints, and he and Burke have been off somewhere looking at them for some time. Meredith feels as thought she is no longer part of any of this, but is watching it all unfold from the observation gallery instead.

She wonders what Derek is doing now. Does he have other patients to look after, or is he just sitting by himself? She wonders how Bailey's husband is doing? And Bailey? How are they all doing? But mostly, she wonders about Derek. Not just what he's doing, but what things would have been like if Addison had never existed, if there had never been a Derek and Addison. Would they have gotten married; had kids? What would their life be like now? What would it be like twenty years from now?

Meredith has never really thought about her future before. She's never really envisioned herself having a family or getting married, or even falling in love. Did she want married in a church wearing a white dress, or would it be a simple thing at City Hall? How many children did she want and what would their names be? Boy or girl? Pets?

She and Derek never met each other's families or talked about them much, but she knew that he had four sisters and quite a few nieces and nephews, and he knew about her mother. Meredith wonders what Derek's family is like. Would they have gotten along? What would her mother have thought about Derek?

"Dr Grey!"

Meredith looks up and freezes. Derek Shepherd is standing right next to her, dressed in full surgical gear. She must be imagining this. Derek isn't here; he's downstairs. She's up here, all alone, touching a bomb.

"Dr Grey, if you're not going to pay attention, I'm going to have to ask you to leave the OR." There was a teasing note to Derek's tone; obviously, there is something she is missing.

"Right," she mumbled, looking down at the exposed brain in front of her. A subdural hematoma. Relatively simple to deal with; certainly a procedure both of them have done before. The patient is a teenage girl who had… Meredith can't remember why the girl is here; what caused her hematoma? She can't ask Derek, he's already teasing her for not paying attention. How did it happen? It was early this morning when Derek got the page…

"What time is it?" Meredith mumbled, closing her eyes briefly and sinking back onto the pillows.

"What? Are you tired?" Derek teased, rolling over.

"No, I just wondered how much time is left before the alarm goes off…" Meredith doesn't want to admit it, but she is tired. As great as last night was…

"It's six o'clock. I turned off the alarm last night, remember?"

Meredith groaned. Six o'clock. She was going to have to get up soon or be late for work.

"You are tired!" Derek chuckled; Meredith's fatigue was obviously highly amusing to him.

"So are you," she countered. "I haven't been having sex with myself all night."

Derek pretended to pout. "That would be no fun."

"No fun for you," she corrected. "I'd be enjoying myself."

Derek shook his head, grinning. "Well, since there's no point in going to sleep…" he broke off, rolling back on top of her and beginning kissing her neck.

"Let's just skip work." Meredith was more than content to just stay here all day where it was warm, safe, and full of Derek. Work could be a scary place, what with Addison and the Chief...

"Mmm," Derek mumbled into her neck. His hands and tongue roamed everywhere, making Meredith burn with desire.

BEEP!

Meredith wanted to scream as Derek's pager went off. With a sigh of frustration, Derek rolled off and snatched it up. "911. I have to go." Derek crawled out of bed and began pulling on clothes.

Meredith combed a hand through her hair and tried not to scream. Things like this seemed to be happening way to often these days: they'd be in the on-call room, or the stairs, or the elevator, and someone's pager would go off.

"Come with me."

Some of the frustration dissipated as Meredith considered Derek's offer. Surgery was the next best thing. And if she did go, they could continue there they had left off when they had a spare moment…

With a sigh, Meredith heaved herself out of bed and began routing around for clothes. May as well go. Cristina would probably be there, either in the skills lab or trolling for surgeries. Not only that, but this was obviously going to be a rare procedure; you didn't page the head of neurosurgery at six a.m. for a couple bleeders.

"Did they say what it was?" Meredith tumbled down the stairs and into the kitchen, where Derek was two travel mugs with fresh coffee.

He shook his head. "Have some toast."

"Toast?"

"A healthy breakfast is the key to a successful day, Mer," Izzie chided from the stove, flipping pancakes like a pro. Meredith started, she hadn't noticed Izzie or George, who was sitting at the table with a large glass of orange juice and an empty plate that was obviously awaiting Izzie's pancakes. "You're obviously going to need all of your energy this morning," Izzie continued. "Looks like it may be a long surgery."

Meredith glanced at Derek and raised her eyebrows. He said nothing, just glanced at the plate on the counter, bearing a small stack of buttered toast, indicating she should probably take one. She shouldn't even have asked Derek; he was a breakfast person, a habitual breakfast eater. To satisfy them all, she grabbed a piece and headed out the door, calling a hasty, "See you at work!" to Izzie and George as she went.

As soon as they got in the car, Meredith shoved the toast at Derek.

"You really should eat." He frowned slightly, keeping his eyes on the road.

"I don't do breakfast, Derek, and besides, I'm not hungry." Meredith didn't want to have this discussion.

With a sigh, Derek took a bite of toast. He looked for a moment as if he might say something, when Meredith's phone rang.

"Where is Shepherd?" Cristina didn't even need to announce herself.

"Driving."

"You're coming too?" Why did she even need to ask? Meredith wasn't the type to skip out on a cool surgery; Cristina of all people should understand this.

"Yeah. We're on our way."

"Okay. Hurry up." Cristina hung up without another word.

"Was that Cristina?" Derek asked.

"Yeah." No one else would be calling her so early.

They chatted about simple things for the rest of the ride: current news stories; the latest Sea Hawk scores; the weather forecast for the weekend. There was no talk of surgery, or friends, or Addison. It made Meredith forget that there was a big trauma coming in, that someone out there was dying. With Derek, it was so easy to pretend that everything was okay.

Derek didn't park the car out front; he drove straight to the ER instead. It felt so weird to be entering the ER in ordinary clothes; it made Meredith feel like a patient and not a surgeon.

"What have we got?" Derek was all business. He looked like a surgeon, scrubs or no scrubs.

"Car crash." The ER nurse explained how the girl had unbuckled her seat belt to get something in the backseat, and had ended up pitching through the windshield. Cristina had taken her up to CT.

"All right. I'll go upstairs and take a look. Oh, and Dr Grey and I need scrubs," he added.

The nurse looked slightly put on the spot; it was obvious that she was busy.

"I'll get them," Meredith offered.

Derek blinked, surprised. "You sure?"

"Yeah. I'll meet you at CT."

Derek smiled, and kissed her quickly. "Better hurry up, Dr Grey. You and I have unfinished business to attend to."

Sex and surgery, Meredith thought, as she headed off upstairs. The day wasn't shaping up to be so bad after all…

The sound of the door opening snaps her back to reality. It's hard to keep her face neutral as she suppresses the crushing disappointment that reality brings. There is no subdural, no surgery and sex, just her and bomb that could go off at any moment.

Burke and Young are standing in the doorway, whispering to each other. Both of them keep looking at the floor and then at her. Something's wrong. As much as Meredith is trying to be happy and glass half full about this whole situation, she has a gut feeling that something is really wrong.

Meredith can't take it anymore.

"Stop it." Both of them look at her in surprise. "I'm not a patient."

"What?" Young frowns, confused.

"The two of you are looking at me like the way we look at patients, like I'm going to freak out at any minute. I'm not going to freak out, so whatever it is, just tell me straight out," Meredith explains, frustrated that they insist on keeping her in the dark.

Neither of them say anything for a minute. Finally, Burke turns and crosses the room towards her slowly, as if he is choosing his words wisely. "The main oxygen line runs directly under this room."

"Okay." Burke doesn't say anything; he just continues to look at her with that grim look on his face.

"Not okay." Meredith tries to remember to stay positive.

Still Burke doesn't say anything.

"Well?" Nobody says anything.

Meredith takes a deep breath. "I need one of you to tell me what this means exactly, because I think I know what it means, but I tend to be glass half empty these days, so I won't trust what I think it means, because what I think it means if that if the bomb were to explode over the oxygen line, the whole hospital could blow up. And that's just crazy, right?"

Their silence tells her everything she needs to know.