((I do not own the shows Sherlock, Doctor Who, or any of the characters taken from them.))

TEXT FROM: SHERLOCK HOLMES
22:41
Come to the flat.
SH

TEXT FROM: JOHN WATSON
22:42
why

TEXT FROM: SHERLOCK HOLMES
22:42
Fake police box just crashed through the window. Man fell out.
SH

TEXT FROM: JOHN WATSON
22:43
right sherlock if youre just going to make up smthg at least make it believable

TEXT FROM: SHERLOCK HOLMES
22:44
Hurry up.
SH

John arrived just over five minutes later, more than a little irritated. Climbing the stairs, he found the situation as it had been described: a big, blue, wooden box proclaiming "POLICE PUBLIC CALL BOX" was sitting in the middle of the room, surrounded by smoke and the scattered glass from the window. A thin young man in a light blue shirt and tie was lying on his back on the floor, coughing.

John crouched down near him, waving the smoke away with his arm. "You alright?" he asked.

The man sat up with a start, then dropped his head into his hands and groaned. "Never … semi-sentient time ship … 'crash for the night'," he muttered, then looking up at John and with a much cheerier voice, "I'm fine, honestly. Just hit my head a time or two, and a bit of smoke in the lungs. I'm the Doctor, by the way. And you are?"

"Dr. J–" "John, sweep up the glass, if you would." Sherlock emerged from behind the box with his figuring-things-out look on, signaling that he'd like a turn with the visitor. John shot a look which Sherlock knew meant "go easy on this one" – a request that he knew would never be heeded – as he got up.

Sherlock bent down until he was staring directly into the Doctor's face, taking in every little detail of the strange visitor. Appearance says mid-twenties, eyes say much older. Tries not to show negative emotion, but eyes show bitter guilt; has been such for a while, but aggravated recently. Stood in the rain — he reached out and wet his index finger on the man's damp hair, then sniffed and licked it — London rain, less than thirty minutes ago —from a parallel universe; shirt-front wet, was wearing a suitjacket; did not protect himself from the rain; was preoccupied. Double pulse in neck; two hearts, not human, although is accustomed to human company, based on dress and language.

Sherlock stood up. "Doctor. You're an alien time traveler from a parallel universe, and this box is your ship, disguised to look vaguely like a 1960's phone box. May I go inside?"

The Doctor — his expression, Sherlock noted, now registering amazement, skepticism and – fear? — got up and opened the door, allowing Sherlock in. He walked slowly around the central console, pulling out a pocket magnifying glass to examine the different controls. Designed for six pilots, but he travels alone; five sets of human fingerprints, recent, plus at least two more on the railings; close friends, otherwise wouldn't have let them, untrained, work the controls; none here now. Traces of tears at one place; she? definitely she — didn't want to leave, but he made her anyway – Sherlock frowned, remembering the bitter guilt and loneliness he had seen in the visitor's eyes. Suddenly feeling slightly out of his depth, something he didn't feel very often, he returned to the doors, from where he knew the Doctor was watching.

The Doctor felt uneasy around this man. This man could figure out that he was from a parallel universe just by tasting the rainwater in his hair. That's brilliant, that's – that's proper genius, there. But now he had let him into his TARDIS, and who knows what he'd find in there."Who are you?" he asked, turning to face the stranger.

John had just finished hanging one of Mrs. Hudson's quilts over the open window when the Doctor tackled him from behind and spun him around, madly searching his eyes and face. "He's – Sherlock Hol – Wait, John – John Watson? The John Watson? But you're not – you're not real, you're fictional!—"

"Do I look fictional?" John retorted, folding his arms as if he'd been insulted. "And how do you know my name? Have you been reading the blog?"

The Doctor stepped back, moving his hand to the nape of his neck as he spit back out the word he'd just heard. "Blog? What? No. No – What year is this?"

"2011. How do you not know that? What are you on about?"

"John. He's an time-traveler from a parallel universe. Obviously, since he landed here by accident, he might not know the date," Sherlock put in.

"I've — missed something, haven't I."

"Hang on, hang on. Is this – 221B Baker Street then?" Neither John nor Sherlock had any chance to reply, as the Doctor was already leaping down the stairs to the front door. Following, they found him gaping around, bewildered, at the rest of the street, twirling on the sidewalk, his long coat — where'd the coat come from? John wondered — swinging, both hands to his head now —

The Doctor came back to the door, where Sherlock and John were both staring at him like he was some sort of madman. There was something very, very not right about this. Sherlock Holmes doesn't exist. He was made up by Sir Arthur Conan Doyle in the 19th century. Sherlock Holmes is a fictional character. Sherlock... He grabbed Sherlock by the arm, searching his eyes just like Sherlock had done to him not ten minutes earlier.

He's not pretending. He's – well, he is definitely clever, he just told me all about my life, my ship, and my friends — he winced slightly, remembering the ease and the apathy with which Sherlock had just told him what he had figured out about Donna – how did he know about Donna? That was only two or three hours ago, haven't even talked to anyone since then – well, Wilfred and her mother, but they're hardly ones to go talking to parallel-world Sherlock Holmes actors – ha! no, he is really that clever – is he? he can't be, no human should have tha—

"Doctor?" John's voice shook him out of his musings. Realizing how hard he was gripping Sherlock's arm and how intense his stare must be, he shook his head and let go. "Sorry. Train of thought got away from me there. Um, yes. No, you do appear to be very real. Uh, do you perchance have a computer I could use for a moment? Need to look something up."

Five minutes later, the Doctor, sitting in John's chair, had found no online evidence whatsoever of Arthur Conan Doyle, his Holmes books, or any other Sherlock Holmes besides the one who was standing over his shoulder, watching in puzzled fascination as he sonicked the laptop to get results faster. John had gone to bed, evidently not wanting to let on that he was completely baffled and slightly irritated by the whole thing, especially since Sherlock seemed to be completely unfazed and probably, knowing him, even enjoying it.

The Doctor stood finally, stretching his lanky frame. He knew he had to go – the hole he'd fallen through into this universe probably couldn't last long, and he didn't want to get mixed up in the affairs of a parallel world like he had last time. "I suppose I'll be off now, um, get the TARDIS out of your flat and out of this universe, it's really not good for her, although I did stock up on power cells because last time I was almost completely stranded —"

"Take me with you." Sherlock's voice was calm but determined.

"— I can't." The Doctor, knowing he would have had to make this decision, still hated the words the very second after they had left his lips. But he couldn't, he just couldn't let himself risk losing anyone else, especially not Sherlock Holmes.

"Yes, you can." Sherlock, his eyes never leaving the Doctor, reached down to his pocket and pulled out a small object. The Doctor glanced down at it curiously, then his eyes widened and darted back up to Sherlock, who had let himself crack a small, almost mischievous smile. A Cheshire-cat-like grin slowly spread over the Doctor's face. Sherlock Holmes, you brilliant, impossible man!