I do not own Sherlock (neither the BBC version nor the original book series or any of the interpretations). I also do not own "The Cat That Walked By Himself". This story begins during season 2 episode 1, the Scandal in Belgravia.

I loved the interaction between Irene Adler and Sherlock, but felt it could have taken a very different direction if she wasn't working with Moriarty, so this story is my "what if" about Sherlock meeting someone similar but different instead. Eventually Sherlock/OC/John.

Huge thanks to Blue Dot77 and Alice Bekett for all their support.

Sherlock was in Buckingham palace, in a sheet. Which amused both Watson and himself somewhat; leaving them in a jovial mood by the time Mycroft arrived. The elder Holmes brother on the other hand was not quite so cheerful about Sherlock's attire, or his attitude. The meeting between the three of them and a gentleman by the name of Harry was not going well, even before Sherlock decided to throw a Diva tantrum and storm out the room because they wouldn't tell him who wanted to hire him. Mycroft's shoe came down on the trailing edge of his sheet, bringing him to a halt as he scrambled to hold it about himself.

"This is a matter of national importance. Grow up." Mycroft growled softly, hoping not to make this into more of a scene than it already was proving to be.

"Get off my sheet!" Sherlock demanded.

"Or what?" Mycroft's sibling rivalry with his younger brother snuck into his tone despite his best efforts, reducing the pair to squabbling children. Watson took a deep internal sigh.

"Or I'll just walk away." Sherlock threatened.

"I'll let you."

"Boys please..." Watson began to interrupt them when a figure entered through the door, blocking Sherlock's exit.

"Oh do call his bluff Mycroft." The young woman's hazel eyes swept over the detective appraisingly, causing Mycroft to lift his foot and Sherlock to wrap his covering back about himself. "Spoilsports. Oh don't look at me like that." She spoke to Mycroft as he glared at her, clearly unhappy with her playful tone. "I brought you a present." She winked, pulling a phone from her pocket. His eyes lit up, interesting Sherlock and Watson.

"Is that what I think it is?" Harry asked from the back of the group, reminding everyone that he was still there.

"No, it's a piece of cheesecake." Her sarcasm brought a smile to John's face, which he quickly squashed.

"How did you get it?" Harry asked.

"More importantly how did she know we wanted it?" Mycroft muttered as he reached to take the small plastic object.

"I keep my ear to the ground, you know me. That is the second thing I have given you that you have wanted, so now I may warm myself by the fire for always and always and always and yet still I am the cat who walks by herself and all places are alike to me." Mycroft scowled at the slightly paraphrased quote, he scribbled on a piece of paper and handed it to her. "Thank you."

"It'll take a few days for me to set it up." She nodded.

"I'll tell my employer everything's settled. If you'll see them out?" Harry spoke to Mycroft.

"Yes of course."

"So you dragged me all this way for nothing? I should have known." Sherlock complained his eyes narrowing. "And what precisely was with the Rudyard Kipling reference?"

"Never mind brother. You can go home now, and for goodness sake try and wear some clothing next time I see you."

"Aren't you going to introduce me first?" The woman smirked as Mycroft tried to hustle them out the door. She strode over to pick up Sherlock's clothing, handing it to John.

"Sorry, I'm John Watson." He commented, ignoring the glare from Mycroft, he held the clothing with his left hand and proffered his right for her to shake.

"Sophia Thompson, so is the great Sherlock Holmes..." she gestured over her shoulder to where he stood, "quite as arrogant, difficult to work with, irritating and brilliant as his bureaucratic twisted genius of a brother?"

"Definitely," Watson replied with a tight smile and his dry humour.

"Splendid. Let me know if you need anything, I can achieve and acquire some rather impressive things if I put my mind to it." She gave him a card. "Of course nobody does anything for free but I'm sure I can give you a very favourable deal, similar to the one I have with Mr. Holmes the elder." She walked towards the door. "I look forward to hearing from you John, oh and Sherlock," she paused by him as she passed, "feel free to continue to consider clothing optional should you want to." She waved as she left. There was a brief silence.

"Wow." John broke it with a slight shake of his head.

"What exactly did she mean by the deal with you?" Sherlock asked, his eyes focusing on his brother.

"Not now Sherlock. I have some rather delicate arrangements to make. Just try to avoid needing her; I'd hate to see her get her claws into you."

"I'd rather like to know who we're dealing with."

"The price for the first gift that she brought me, one which might I add saved the lives of a good number of very important agents in key positions, she asked for diplomatic immunity and her records to be wiped. She said that it was to be brought in from the cold, into the cave so to speak in her ever so charming way of relating our arrangements to a children's story. I won't tell you what this phone cost, or what it could have done in the wrong hands, but the price was also very steep, one she knows I find myself required to pay. I can only assume the things she might ask of you may be just as... dramatic."