"Shut your eyes!"
Sherlock obeyed for reasons he couldn't quite understand, but then, he hadn't started out the morning intending to dive off a roof either. The landing, when it happened, was several seconds too early, and much gentler.
"Foam pit!" announced the same voice. "You're free to open your eyes now. Didn't want to get small chunks of foam in your eyes. Not with the nap you're going to take." When Sherlock did open his eyes, the man in front of him was still babbling, hand outstretched. "Come on, come on, haven't got all day."
Sherlock allowed the man to pluck him from among the chunks of foam, and set him on his feet.
"Do I..." he began, and the man seized the opportunity to gob again.
"Know me? No. I'm the Doctor. But I know you. I'm a fan, not the kind who reads John's blog and wants you to wear the hat. I do like it though, like hats in general. Not the point though. Oh!" he smacked his palm against his forehead. "We're running out of time."
He grabbed Sherlock's hand and half hauled him through the corridors. This Doctor was officially the most annoying hallucination he'd ever had.
"You haven't used and you're not unconscious. Well, not yet," supplied The Doctor, answering Sherlock's thoughts, as they skidded to a stop. "I'm absolutely real. Just as you are. In this universe anyway. In some others, you're just a story, or a character on the telly. They're all brilliant, but it's good to meet you."
"Must you talk so much?" grumbled Sherlock.
"Yes. Now, listen." The Doctor clamped a hand over the young genius's mouth. "I'm here to help you fake your death. We've got to be convincing down there. This version of John won't accept a half job, and I've seen you do this your way, you end up badly injured, so here to help." The Doctor slowly removed his hand.
Sherlock's eyes narrowed. "I should have bitten you for that. Wait, you've seen me jump?"
"Time travel. Don't scoff. Scoffing is for normal people without an understanding of advanced particle physics."
"I'm not?"
"You're definitely scoffing," returned the Doctor, and Sherlock noticed that this Doctor looked at him the way Molly did, sometimes.
"I really am sorry about this," The Doctor whispered, and stepped forward, carding Sherlock's curls in his fingers until he had a good grip.
Sherlock began to fidget. "No touching."
When the Doctor spoke again, his voice was firm and Sherlock found the command impossible to disobey. "Hold still."
Then he leaned in and knocked their heads together. Sherlock was unconscious in an instant, his mind swirling with the Time Lord's memories to occupy his brilliant mind while he slept. Mathematics humanity had never seen, physics of planets made of powder, and creatures living in a wisp of gas. The birth of the universe. The Skasis Paradigm, the Lazarus machine, and the Key to Time itself.
"No need to be bored yet, clever boy. Still a lot of work to do," murmured the Doctor. Carefully, he eased Sherlock down to the grating, and arranged his body according to the picture in his memory. A few pulses from the sonic meant Sherlock wouldn't rouse too early. The Doctor knelt in front of the temporary corpse, and brushed a kiss to Sherlock's nose.
"I imagine this is how Friar Lawrence must have felt," he muttered aloud. "Alright, time to return you to John."
And in the crush of chaos that followed no one noticed the sound of time rotors as an invisible TARDIS dematerialised and left behind Sherlock.