Author's note: 'Curious Incident' is obviously an AU in the most specific way possible-it is literally an alteration of the Sherlock universe. But I have to admit, I still haven't seen S3 (soon!) so I don't know in which ways the show contradicts me. (Except for the absence of Dr. Who, of course...)

By the time they drove up to Mycroft's house in Mayfair it was already dusk. There was a tiny parking strip close to his door that was large enough to accommodate Donna's Mini-Cooper—but only just. Emerging from the passenger side of the car, he tapped out a code on his mobile to temporarily deactivate the three nearest CCTV cameras. He didn't want to leave a permanent record of their arrival.

This mews house was the only place left in the world that Mycroft Holmes could still call 'home.' It was a sometimes awkward combination of the antique and the modern—wrought-iron gratings over bullet-proof glass windows, weathered brick walls protected by a shiny-new security system. He tapped his mobile again to unlock the front door and turn on the downstairs lights.

"My family has owned this place since the early Victorian era," he informed his companion with unconcealed pride. "It's the only Holmes property left from the old days. Everything else went to the death duties."

Donna had just hauled a bulky Burberry bag from the back seat and was scanning up and down the quiet street. "Your family's lived here for a hundred and fifty years? That's pretty impressive."

"We didn't start out living in it," Mycroft admitted. "It's a mews house, so it began as a stable, but after it was converted, yes. Most of my neighbors have been here for decades. So far we've managed to keep out the absentee Saudis, although we do have a millionaire, a cosmetics CEO, and a hedge-fund manager."

"But your brother has a flat in Baker Street."

Mycroft gave his head a rueful shake, then ushered Donna into his home before the CCTV cameras could flick back on. "Of course he does. Sherlock would never dream of residing under the same roof as me."

The décor in the foyer was somewhat old-fashioned and stuffy, but Mycroft liked it that way. The original wallpaper had not survived the installation of the new security setup, but fortunately Anthea had found a paper with an almost identical rose pattern. He waved vaguely down a hallway lit with bright LED lamps in refurbished gaslight sconces. "The dining room and kitchen are to the left; the parlor and the library are on the right. Make yourself at home in the parlor and I'll bring us espresso."

Hoping that Donna would not pursue him into the kitchen, Mycroft departed to the left. His espresso machine was supposed to be foolproof but sometimes he had to fiddle with it.

After a few moments he joined Donna in the parlor, wheeling two cups and a coffee service on an antique Georgian tea cart. She had placed her bag on the Hepplewhite sofa and was examining the pictures on the far wall.

"Two lumps, no cream, right?" Mycroft asked. When Donna gave him an exasperated glare he added blandly, "I watched you drinking coffee on the commissary CCTV."

"You have quite the eye for detail, Mycroft," she replied with only a slight edge to her voice. Sitting down on the sofa, she accepted the cup from his hands. "I was just wondering—why are there no portraits of your family in the parlor of your old family home?"

Mycroft sat down beside her and glanced around at the walls. The pictures he'd hung in the parlor were duller than dull; even he found it difficult to recall them. A watercolor of Mont Blanc, two black and white photos of wizened pine trees, and a very plebeian oil still-life of three lemons in a basket.

"Because I sometimes entertain my colleagues in this room."

Donna added her two lumps of sugar as she considered his statement. "You're a very private sort of a man. Maintaining complete control means everything to you, doesn't it?"

Mycroft tossed three sugar lumps into his own cup and stirred fiercely. "In a word, yes."

Pursing her lips, Donna thought about that for a while and finally said, "I'm so sorry, Mycroft. What I put you through there at the tennis court—it must have been the worst thing that you could have possibly imagined."

"You weren't the one who put me through that." Mycroft was pleased to notice that when he replied, his voice was completely controlled.

"I suppose not. If you'd just let go of my hand you probably wouldn't have been pulled into-" Donna stopped dead. "You can't be blaming the TARDIS—it's just a machine, you know."

Rolling his eyes in haughty dismissal, Mycroft didn't answer.

Donna kept on digging. "The Doctor? You blame the Doctor? I should think that you'd understand better than most that it was a life-or-death decision no one else would make—that no one else could make."

"Yes, he saved the universe," the beleaguered bureaucrat snapped. "I know that. Fine. I'm sure I ought to be grateful."

Mycroft set his espresso cup down onto the floor so he wouldn't spill it. His throat had closed up and he could feel his hands shaking.

Donna's voice was calm but intense. "Tell me what's hurting you."

He flinched, but said nothing. What could he possibly say?

"You've got to let me help," she said to him.

But he was a private sort of man—hadn't she just told him she understood that?

"If you don't tell me," Donna went on relentlessly, "then who can you tell?"

Mycroft could feel his ice shattering all around him, he had nothing left to protect him, and worst of all, she was absolutely correct. There was no one else that he could tell.

Dropping his hands onto his knees, fingers splayed, Mycroft started to speak in a voice that was almost inaudible.

"Back there at the tennis court… I was positive that I was about to be deleted. Not merely killed or destroyed, but erased, obliterated, turned into a never-was. It never even occurred to me that the universe could be rebooted and that I—a man whose mind had been uniquely shaped by that specific universe—could possibly survive."

He sat silent for a moment and looked down at his trembling hands.

"And the fact is, I still can't believe it. The Mycroft Holmes in that tennis court had never gazed up at a star, had no idea what the word 'constellation' meant, had never imagined the concept of a space program. The Mycroft Holmes of this world has always taken these things for granted."

Mycroft stared into the eyes of Donna Noble, the only woman in the universe who could possibly understand what he was talking about. Her eyes were almost as remarkable as the woman herself—their irises were double-ringed in blue and brown.

"So tell me, Doctor Donna. Which Mycroft Holmes am I?"

Donna's eyebrows lowered in a frown as she tried to puzzle out an answer. She wasn't about to let him go down without a fight. When he realised that, Mycroft couldn't help but feel a little hope.

After thinking hard for several moments, she ultimately told him, "You're both of them. I don't remember how this timey-wimey business works, but I know you're both of them."

She placed her palms on top of his hands, and disconcerting though it was, the sensation of warmth on his frozen fingers was rather comforting. "I don't believe that you're worrying about the Mycroft who grew up in this world—the man that you're worried about is the Mycroft from the World Without Stars. But the man who was in the tennis court is the man that I met! I can remember him, can't you?"

Staring right back at him, she ticked off her explanation point by point.

"I remember how he invited me to walk out with him on that bloody hot day and then tried to pull the wool over my eyes."

"I remember when he met an alien time machine that was smarter and more powerful than anything he could have ever encountered—and immediately started to argue with it."

"I remember that he held me tight as I lay there dying and never let me see that he was scared."

"I remember that man perfectly and he's sitting right beside me!"

Mycroft didn't believe for a moment that he would accept what was essentially an ad hominem argument from anyone but his Doctor Donna—but he would accept it from her. She'd been through it all and she understood what he'd been through.

He'd always known that he was a stubborn man, but at least he wasn't a stubborn fool. "You're right. I remember that man too," he said with a sigh, enveloped all at once by an incredible sense of relief.

Donna smiled brilliantly and threw her arms around him in a joyous hug. She had pulled him out of black horror and that was triumph enough for her. It was so very like her.

But before Mycroft could react, he felt her shiver and crumple in on herself. What was going on now? When she looked up at him again, he could see in her haunted eyes that a memory she'd managed to push away from her had shoved forward to attack.

Whitefaced, she muttered almost inaudibly, "Oh Mycroft, I can remember it all now. I was dying and it was horrible, so horrible..."

Mycroft grabbed at her hands to steady her, but Donna pulled them away and covered her mouth with a trembling fist. "You were afraid because you thought that you were going to be deleted, but I knew that my body was dying and that my spirit wasn't being drawn into the light. I could feel my mind being uploaded into the TARDIS Matrix. I was being turned into a machine!"

He should have known, Mycroft told himself bitterly—of course there would be still more horrors to come. He couldn't even imagine what it would feel like to be absorbed by a computer. If that blasted Doctor had been just five minutes faster…

Donna needed his help, and for a blessed change, this time he knew how to cope with another person's feelings. What she needed right now was someone to hold her tight and prove to her that she wasn't alone. He could do that for her and he would do that for her. Without bothering to analyse the situation further, Mycroft put his arms around her and squeezed. She stopped quivering almost immediately and allowed her weary head to sink onto his shoulder.

"You're not a machine, Donna Noble," he whispered fiercely. "You're a woman, and you're alive, you're so alive."

In spite of everything that had happened to him, Mycroft realised that he felt… content. The stars were shining in the sky exactly as they were supposed to, the Earth was revolving safely around the Sun, and the woman in his arms was not likely to die any time soon. Somehow things would work out.

After a little while, however, he began to worry whether Donna might be feeling a bit embarrassed. It would be so like her to fret—she never wanted to appear needy. She was almost like Sherlock in that respect. On the spur of the moment, he tilted up her chin with his thumb and two fingers so he could see the expression on her face—

—and to his complete surprise, Donna lifted her chin up still further and kissed him right on the lips.

Wait, what? He hadn't intended this at all! But he couldn't say that to Donna. Good heavens, it would completely humiliate her.

When Mycroft looked back at the things that he'd done in either of his two lives, what he most regretted were the times when it simply hadn't been possible to give the people he cared about whatever it was that they wanted. But this time he could. Donna didn't want him to overturn a perfectly rational decision—she just wanted him to kiss her.

What he wanted was to have Donna put aside the dreadful experiences she'd endured—that they'd both endured—and to make her believe that life was still worth living. That's what they both wanted, really.

After a second or two of thought, Mycroft framed Donna's now-nervous face with both hands and pressed his lips quite deliberately on the center of her forehead, on her closed eyelids, and finally on her own lips. The corners of her mouth came up in a sweet smile.

That was Donna for you—when a man showed that he actually appreciated her, it always made her feel happy. Mycroft kissed her lips once again.

Up close, her hair smelled like violets and her lips were wonderfully soft. Kissing Donna would be no trouble. One of her hands crept up to trace the edges of his own lips and without thinking, he opened his mouth and touched his tongue to her finger.

Mmmmmm…...

It had been longer than Mycroft liked to admit since his last impromptu snog on a couch, but he still remembered the procedure. First, you made sure that the girl was comfortable. You made some innocuous small talk, you cuddled her a little bit, and then you moved in.

Leapfrogging unknowingly to Step Two, Donna whispered into his ear, "Oh Mycroft, I'm so glad that you found me."

Mycroft, however, was still mired at Step One. He was trying to get comfortable and the authentically-restored Hepplewhite wasn't particularly ergonomic. He was sure he'd be all right, though—for the first time in days, he wasn't being gnawed by doubt and worry. Sliding his arm around Donna's waist, he sighed with relief. "I thought that I had maimed you. I'm so very glad that I didn't."

When he realised what he'd just said, Mycroft froze in horrified embarrassment. Upon what planet would something like that constitute small talk? He wanted to kick himself—hard—but Donna just laughed and murmured, "Shush."

And then she kissed him again.

One kiss led to another, and then another. By the time he and Donna finally surfaced for air, they were both panting and overheated. If they continued much further along this road, there was a real chance that he might forget himself.

The part of Mycroft's mind that never stopped evaluating tactical scenarios had an immediate answer for that. Forget himself? If there was one thing that he needed—that they both needed—it was to forget themselves. Even if only for a night.

When both his intellect and his instincts agreed, it was a reasonable assumption that they were correct. Taking a deep breath, Mycroft nerved himself up to the fullest, deliberately dropped his self-control, and let himself go.

It was a very strange thing to allow his feelings to rule him, but it was what he had made up his mind to do. One of his hands was soon blindly wandering down Donna's body, while the other rose up to fondle her breast. He wanted to touch her all over—he wanted to know all the parts of her that his memories didn't cover. Right now he even wanted her to know him.

Clutching Donna even tighter, Mycroft mumbled, "I don't believe that I mentioned anything to you about the upstairs floor."

"Are you crazy? Why are you bringing that up now?" Donna grumbled into his neck. Then she sighed in resignation. "All right, I'll bite. What've you got upstairs that's so important?"

"Umm… bedrooms, mostly."

Donna's eyes shone up at him like stars. "Why don't you show me one?"