Hello there peoples! Here's a Sherlock and Doctor Who crossover, I hope you enjoy it. I haven't decided yet weather or not to continue it or just leave it as a one shot. Tell me what you want and I will do my absolute best not to disappoint.

Speaking of disappointment... The next chapters for John Watson or Arther Dent, Sundays in the Backyard, Boy in the Water, Boy on the Land, and John's Drabbles are all in the process of being written. All of them are started but my muse hit me with something original so I've been concentrating on that forever. I hope you understand that when your muse hand you something good you follow.

Anyway, thanks for sticking with me.

Title: John, That's Impossibl-

Warnings: None

Rating: K

Words: 1,511

Disclaimer: All recognizable characters aren't mine. Except in my dreams.

Sherlock wasn't sure what compelled him to search John's room. It could have been curiosity to what, if any, secrets John had been able to keep from him. (Though he really doubted it.) He knew the basic, surface level stuff, obviously. But he wanted to know more. With John, nothing ever seemed to be enough. He had been living with the man for a while now and he still surprised him … sometimes.

Through all the want to figure out the puzzle that was John Watson, Captain and Doctor, Sherlock, deep in his mind, hoped that he would never figure him out completely.

He pulled a decent sized box from the closet; surprised at its weight he dropped it on the bed. Opening the worn cardboard and inspecting the contents Sherlock made several quick deductions.

Dried tear stains, ripped slightly at each corner-used to be opened often in times of emotion/stress/anger.

Slightly dusty when first pulled out-not opened in a while. NOTE: why? END NOTE

Fingernail imprints on the inside panels of the lid- Gripped hard and with little regard for self-pain, most likely in response to the contents due to placement of marks.

Conclusion- something John cares for, (sentiment), not opened since we meet according to the dust, something that caused deep or old emotions. NOTE: To answer above 'note' inspect contents. END NOTE

NOTE: Sentiment-not for experiments, do not break. END NOTE

The first things inside the box were several small packages wrapped in tissue paper which when opened, Sherlock found, contained old, scratched and stained dog tags. One had the metal warped, twisted and dinged at one end; this one also appeared to be stained.

Blood stain. Lots of blood. Looking at the scaring on the metal….The bullet that shot John also chipped the end of this.

Upon a closer inspection Sherlock found that some of the metal was indeed chipped of.

NOTE: Pushed inside John along with the bullet? END NOTE

Sherlock laid down the tag next to the others on the bed and reached in for the next item, making a mental list as he went, more and more surprised at each one.

George Cross (G.C)

Distinguished Service Order (for command and leadership-obvious, this is John).

Mention in Dispatches (Impressive, John.)

Sherlock laid each metal and document on the bed; he had no idea that John was so highly decorated. It was strange for a Captain to have this many awards, but not unheard of.

Strange- going by all the post-nominal's that these awards give him, John's full title would be Captain John Watson, M.D,G.C

NOTE: Why did John never mention this? END NOTE

Under the awards and documents were old letters. They consisted mainly of thanks from the people on leave and family's heartfelt gratitude towards the good doctor that had allowed injured men to return to their families. There were quite a few letters.

And at the very bottom, tucked away in the corner was a blue, thin moleskin notebook the cover of which declared one word: Rules.

"…rules." Sherlock read aloud quietly to himself. He flipped open to a random spot, the pages where timeless – splattered and smeared with substances unknown. He read:

Rule # 27: Never Know Me to be Serious

Never know WHO to be serious?

Sherlock turned to the first page and on the inside cover read in his doctor distinct handwriting.

He wants me to keep a journal like the Ponds. It flatters me a little, but him, Amy, Rory and River went through that together. It wouldn't feel right. I'll know when I am and when they are too, Sexy taught me how my first night.

(Yes, Doctor – that's why I refused to keep a journal like the rest of you lot. Yes I know you're reading this. You're almost as bad as your wife. Hello River.)

But over the years I've learned a few things, the Rules, as the Doctor calls them. This is a list I've compiled of them.

Sherlock was very confused and even re-read the little note.

Doctor who? He can't mean himself – John's not married. The Ponds – these Amy, Rory and River people. Who are they? 'Over the years'?

What can he mean by that, going by the handwriting John wasn't too young. Perhaps med-school. Or just graduated and about to enlist.

Sherlock turned to the first page, he read down at the bottom under a list of other's:

Rule # 408: Time is Not the Boss of You

"hmmm." Sherlock hummed to himself, thinking. He opened another page:

Rule # 42: Nothing is Ever 'Just a Coincidence'

That made Sherlock smirk, whoever this Doctor person was, and he had to agree with him there. He opened the last page, eager to see what the first rule was. At the top of the last page he read:

Rule # 7: Never Run When You're Scared

And finally at the bottom of the last page:

Rule # 1: The Doctor Lies

"Rule # 1," Sherlock heard someone say from behind him, "the most important rule in all of time and space." John walked and snatched the book from Sherlock's hand, glaring fiercely. "The Doctor Lies."

Sherlock immediately bombarded John with questions, the main ones,

"Who's the Doctor? Who are the Ponds? Why don't I know about this?"

John continued to glare and ignored the questions. He looked at his bed and looked at the contents of his dissected box scattered across him.

"Sherlock," His voice was very tight, "what have I told you about going through my things?"

Sherlock refused to back down. "John," he insisted, "What does that mean? Who are those people? What are the rules? What do they mean?"

"Can't you just deduce it?" John snapped out. "God Sherlock, I've asked you time and time again to not go through my things without my permission! This is one of the most precious things I own and I will not take the risk of you experimenting on it with acid or whatever it is the hell you do in our kitchen, got that?"

Sherlock nodded and John's anger deflated, "Just…please Sherlock. This book means the world to me. You probably wouldn't understand – sentiment."

Sherlock nodded again and risked asking another question. "John…what does it all mean? Why, the book, doesn't make any sense. The content or the pages themselves."

Something in Sherlock's voice made John look at him and sigh. "Come along then, it's rather a long story."

"So what you're saying is that this Doctor travels around time and space in a blue police telephone box saving worlds and he occasionally takes humans along with him you traveled with him for a few years?" Sherlock clearly didn't believe a word he was saying.

"I don't expect you to believe me. I know it sounds absolutely bonkers. But it's all true. I did travel with the Doctor. For quite a few years in fact. I left with him after I got my license to practice. And when he left I enlisted. While I was travelling with him I met Amy and Rory and their daughter River."

"But isn't River-"

"The Doctors wife? Yes she is. That's a story for another time though, quite a good one if I do say so myself."

"Oh."

"The four of us traveled together for a time about a year after he picked me up for the first time with River stopping by occasionally. Oh the times we had." John trailed off, lost in memories.

"Anyway," He continued, "The Ponds and the Doctor all keep diaries to keep track of where they are in the time stream. I keep a list of rules."

"You mentioned in there," Sherlock pointed to the little blue book resting conspicuously on the tabletop, "That someone called Sexy taught you how to tell wher – when someone is."

John laughed, "That's the TARDIS – the blue box I mentions. The Doctor calls her Sexy when he thinks no one is listening."

"Tardis?" Sherlock inquired, missing the caps.

"TARDIS," John corrected. "Time And Relative Dimensions In Space."

Sherlock interlocked his fingers and stared at him.

John rubbed the back of his neck, "Look, I know it sounds impossible. But all of its true I swear. Look, I'll have Amy and Rory around next week for tea, yeah?"

"It's strange…"

"What is?"

"You absolutely believe what you're saying is true, but there is no way it can be. It is impossib-"

Vworp Vworp VWORP VWORP

He was cut off and John's face brightened considerably. He lept to his feet and flew to the door, as he passed the threshold he turned back and said, "As a warning, traveling with the Doctor is one of the reasons why I moved in with you. You remind me of him. So I guess you're either going to get along great or try and strangle each other."

Sherlock hadn't moved. John motioned impatiently, "Come on then, I want you to meet him!"

He turned and sprinted down the stairs, Sherlock catching up quickly.

Soooooo? Gimme! What did you think? Should I continue with Sherlock and the Doctor meeting? I've never written the Doctor before and am a bit frightened to, to be perfectly honest.

Thanks for reading and I will continue working on my other fics, I promise I haven't dropped any of them. I only like to work on them when I'm not to busy with my original piece, it's working title is Where the Heron Sits. So when I haven't updated in forever it's because of that.

Forgive?

Love you for reviews and hope this made you're world slightly for full.

JC