"'I'm a time lord, and I'm known as the Doctor.'" John read from his computer screen.

"Reading fanfiction again, John? Your dedication to reading rubbish works of so-called literature is astounding." Sherlock said, turning on the couch so that his back was to John.

"Doctor Who fanfiction is not rubbish!"

"Pah. A humanoid alien that travels around in a police box? Hardly interesting."

"God, Sherlock. I'm buying groceries, need anything?" John asked, closing his laptop and placing it on the coffee table.

"Some sodium bicarbonate-I'm simulating the effects of cleaning agents on human flesh after prolonged exposure."

"Right. What's that?"

"Baking soda, John." Sherlock quipped in his everyone-is-stupid-but-me voice.

"Okay. I'll be back."

As soon as he heard the front door close, Sherlock leapt up and pulled off his dressing robe. Underneath, he wore his signature collared shirt and tailored trousers, over which he pulled on a black jacket that had been hidden under a cushion. Running down the stairs, he stood teetering on the threshold expectantly.

An old, bedraggled, homeless woman with an eye patch turned the corner to Baker Street. As she neared 221B, her drab and stained rags seemed out of place on the picturesque street, but she continued walking, stooping a bit, towards the flat.

"Please, come in. Have a cup of tea." Sherlock gestured towards the open door.

She did not respond, but stepped past him into the flat, Sherlock closing the door before following her up the stairs. Sherlock immediately went to the kitchen, where he located the electric kettle and filled it with water.

"Have any preference?" Sherlock asked as he pulled open a drawer filled with various teas and tea-like herb concoctions.

"What I really want is dinner. But a cup of black tea, thank you." She replied, her voice crisp and friendly, and just a bit seductive.

"You once told me that a disguise is a self-portrait. Are you really a poor, helpless charity case?" Sherlock said as he turned with a tray in his hands.

Gone were the mottled, stained clothes and the elderly walk. In place of the eye patch, her face now displayed a look of satisfaction and smugness.

"Ms. Adler."

"Irene, please."

"I trust you've been well, Irene," Sherlock said, balancing the tray on one hand while clearing papers from the table.

"Do I even have to tell you? Look," She waved her manicured hand at her body.

Her skin was tanner than before, while still looking flawless. She had on beige, drawstring cargo pants and a modestly-cut grey t-shirt, dressed to blend in with the London street-dwellers. Traces of spices floated in the air around her-bits of the makeup she had used to disguise her flesh were also visible, obviously put on before her international flight to Heathrow. Wasn't planning to stay long, she had only packed a few days' worth of clothes. But she had been looking forward to this trip.

"How was New Delhi?"

"Atrocious. I much prefer the weather here in London"

Sherlock silently poured hot water for them, for her the fine-china cup from Mycroft, for him the efficient and shatter-proof mug from John.

"How did you do it?" Irene asked.

"Do what?"

"How did you survive-the fall, I mean."

"Tell me what you think, first."

"Well, you obviously had help. Mycroft?"

Sherlock scoffed, "As if. If Mycroft had his way, I would've stayed dead to the world. Molly Hooper-you wouldn't know her. Decent mind, quite instrumental when one needs a dead body to be buried. She also offered to conduct 'my' autopsy."

"But a dead body can't jump from a roof-"

"No, because I did. Surely you've met my Homeless Network, they're quite willing to do anything, especially if it means getting paid cash to drive a laundry van and ride a bike. They did have a bit of trouble stealing the van, but I made it well worth their while."

"But the body-"

"Looked nothing like me, but a simple flesh mask does wonders for corpse. If you've been keeping up with my cases-clearly you have-then you might know about the ambassador's children and their disguised kidnapper, quite a good flesh mask it was, too."

"Let me get this straight. You took the flesh mask from that case, and put it on a corpse that you got from this Molly girl. Then you pay homeless people to drive a van near St. Bart's, trusting that they'll put enough cushioning to save your life. And you trick your boyfriend into thinking you're a fake, and have jumped to your death. Why?"

"Because, he-Jim Moriarty -would have killed them, my friends."

"Them?"

"John. Lestrade. Mrs. Hudson."

"Not Molly, then?"

"No."

"Why do you ask?" Sherlock said, after a long pause.

"No reason."

"Hm."

"None whatsoever."

"Do you want to have dinner with me?"

"…"Sherlock paused and quirked an eyebrow.

"My new employer is sending me to a posh dinner, undercover. I need a skilled partner."

"Hm," Sherlock appeared to consider it for a second, "Have to decline." \

"It's just one time."

"I know. I'm far too busy."

"I haven't even said when."

"Like I said, I'm far too busy."

"Alright."

They sat in silence, their tea growing as cold as the air between them. Sherlock suddenly stood up.

"Care to see?"

"What?"

"My experiment. The one John thinks I'm conducting right now."

"Why not?" Irene replied, smiling with her lips only.

Sherlock gestured to the kitchen.

The counter was relatively clear, evidence of John's incessant complaining about the beakers and petri dishes, as well as the occasional dead mouse. The stove, on the other hand, was completely covered with a large pot of what looked like water and another pot of similar water-like liquid, which smelled like leather, as well as a Tupperware of something like sugar.

"Dazzle me." She nodded towards the unheated pots.

Sherlock's eyes seemed to light up, and he talked animatedly, his hands moving in a dance as his described his experimentation.

"Right now that is only sulfuric acid. On its own, it barely has a smell. But, it is vital in the experiment as it acts as the catalyst. That there," he pointed to the pot that smelled like leather, "Methanol. Also known as methyl alcohol. I'm going to put that in the sulfuric acid, along with that, (he pointed to the Tupperware) salicylic acid in solid form."

"And what, it's going to explode?"

Sherlock looked as though he'd been insulted, though Irene knew it was simply his dramatic side.

"Hardly. This esterification reaction will produce an ester, or an odorous compound."

"So it makes smelly water."

"Yes. Just like thatChopard Cašmir Eau de Parfum you're wearing is just 'smelly water'. Watch."

Sherlock poured in almost all of the pot of methanol and dumped in the entire container of salicylic acid. When he turned on the stove, a smell like burnt shoes began to fill the air.

"Mh, yes. Just like my perfume."

Sherlock made a noise of annoyance, and then proceeded to turn the heat up higher.

"It's just going to smell worse." Irene said, the disgust dripping from her words.

"Patience, my young padawan."

"What?"

"Nothing."

After a few more moments of the repulsive burnt shoe smell, the odor seemed to dissipate. Before Irene could comment however, a new scent filled the kitchen. It was faint, but this new, minty smell was certainly better than before.

"What is that?"

"It is methyl salicylate."

"Is it mint?"

"Not quite, it's wintergreen. Oil of wintergreen, to be more exact."

"Smells like mint to me."

Sherlock frowned a bit, but his eyes shone with enjoyment. "Yes, that does seem to be what it smells like."

After a few minutes, in which the smell grew stronger and Irene grew more curious, "What is it for?"

"The oil? For its smell. Though I suppose you could use it to cook, if you're not pregnant. Obviously you aren't."

"So observant."

"That is my job."

Irene looked at Sherlock, but he did not meet her eyes.

"Would you like some?"

"What?"

"Some of the oil. You can use it in place of aspirin and for flavoring-"

"I don't get headaches, and I definitely don't cook." Irene interrupted.

"I know you don't, but you do wear perfume. Try this, it won't irritate your skin like that commercial stuff you're wearing."

"How-I'm not even going to ask. I'll take a bottle."

Sherlock dumped out a bottle of what looked like expensive liquor, and used the cleanest pipette to fill it with wintergreen oil. He presented it to Irene with an oh-so-posh flourish of his hand.

"Thank you, Mr. Holmes."

Sherlock barely glanced at his watch before speaking. "John will be returning soon."

He didn't say, but she understood. John wasn't ready to know that she was alive, and it would complicate things for everyone.

"Then I should be going." Irene returned to the living room and began to put on her disguise again.

Sherlock was silent as she donned the ragged jacket and re-applied the unflattering makeup designed to age and disguise her face.

As she stepped out the door, the bottle of oil tucked in her pocket, Sherlock watched her with his snow-colored stare. Just as she was about to turn the corner, he spoke.

"I've changed my mind. I will have dinner with you."

She paused, and then turned. "I don't want your charity, you know."

"And I'm not giving you charity. I will have dinner with you, if the offer still stands."

"I'll think about it."

"Make sure you do."

Three hours later, he received a text.

Yes.

Merry Christmas