It's great to have money again. Means I can go out and buy a proper shop without any disagreements with chip and pin machines. Glorious.

Ok, so I'd rather overdone it that day, but it was too tempting to buy all those Christmas goodies along with enough food for us, and a dozen of our closest friends, to survive a lengthy siege. I'd not really considered the unbelievable amount of doors and stairs that you need to access our rooms.

I had struggled with my key and passed the first obstacle and was now maneuvering what seemed like a twenty plastics bags filled to bursting with the spoils of my trip up the stairs. How had they ever got so long! Sherlock charged up the stairs, pushing past me and the twenty bags to get to the door first. At least that was one I'd not have to bother with.

"Thanks, Sher -" I got as far as saying as the door banged closed behind him with the finality of a gravestone.

I let my loads drop to the floor as I searched pockets for my missing keys, only to find them still in the front door downstairs, luckily still there and not in the pocket of a chancer who'd be up to no good next time we went out. I got back to the top of stairs, a weary man and when I got through the door it did nothing to improve my deteriorating mood to see Sherlock sprawled over his favourite chair with his legs up and eyes half closed.

"You could have held the door open!" I suggested.

"You've got a key - why would I get up out of my chair to go open a door when you can do it perfectly well yourself," he retorted, sounding for all the world as if I'd insulted his mother.

"You were on the stairs when I was coming in, just a moment ago," I pointed out reasonably.

"No," he countered, "I wasn't. Haven't been out all day in fact."

Ok, I'm no consultant detective, but there was pretty conclusive evidence not counting a reliable eye witness account and a certain lack of an impeachable alibi. "So, you got the damp on your turn-ups from watching TV and those traces of grass on the souls of your shoes from boiling the kettle?"

Sherlock down at his ankles as if they had let him down in a terrible and demeaning way.

"And then there's the fact that you are still wearing your outdoor shoes ... and your coat and scarf ..." I continued.

Sherlock yawned like a cat might who's been caught red handed stealing fish from the table in front of a number of diners and is still intent on denying it.

"Oh, that," he said lethargically. "Urgent call by Lestrade. "You were there!" Sherlock looked slightly confused. "Weren't you?"

"No," I said helpfully, "I was out buying your dinner and you didn't tell me there was a case on."

"So, who was that who was assisting me with the investigation?" Sherlock was talking to himself now rather than me. "Wasn't Anderson, not as annoyingly stupid. What she said about the smudges on the curtains was certainly above average-"

"She?" I promoted.

"She - what?" Sherlock asked, looking superior.

"You said, 'she'."

"Did I? So I did. Not-Molly, not-Donovan ... What other females do we know? What other females do we not know?" He looked up expectantly to get my response, which at that point was me groaning and rubbing my hands distractedly through my hair.

"Sherlock, if you want a list then you'll have to narrow it down from women we know, plus women we don't know. Is she a doctor?"

"Has a doctorate, but not a medical doctor."

"Does she work for the police?"

"Yes."

"What capacity?"

"None."

"Then what does she do for the police?"

"Nothing."

"Sherlock, this is going to take a very long time if you're going to be deliberately obtuse. You just said said she works for the police and now you say not."

"You said she worked for the police I confirmed that she did ...", Sherlock looked up at John's irritated face, " ... today, she worked for the police today and rather adequately I might add." Praise indeed for Sherlock.

"Was it 'her'?" I asked, not really wanting to know the answer.

"Your 'her' or my 'her'?" he asked, with a little too much insight I thought, but surprisingly amount of self-realisation.

"Mine," I said bitterly, adding not-mine in my head.

"Sounds rather like 'your her'; let's say it was shall we," he said blithely, kicking off his shoes at the heels.