Disclaimer: I own nothing. Sir Arthur originated, Moffat & Gatiss reiterated. Huzzah.

The past is prologue

13 minutes, 27 seconds (bit different from my day)

When John is five years old, he gets a raging ear infection. His mother, having been through this with Harry, is not prone to panic and holds off on the A&E. But when she finds blood on his pillow she fears his eardrum has burst. She carries him to the car and runs red lights on her way to St. Bart's. It's 2 a.m. when she lugs John into the waiting room where two homeless men are stretched out across the plastic seats and a pregnant woman is being levered into a wheelchair. The woman is gasping, but otherwise perfectly silent. There is a child with her, maybe seven or eight, who calmly answers questions while the triage nurse fills out forms. No sign of the father, and John's mum thinks: poor thing. John is tired, cranky, and screaming while they wait, and his mum has a roaring headache. She tries to distract him by telling him about the little baby in the lady's tummy. She makes him guess whether it's a boy or girl, and of course he chooses boy. After about ten minutes, another nurse arrives and wheels the woman off to a delivery room. John waves goodbye.

7 minutes, 14 seconds (I don't even know your name)

John's in the middle of a very long line outside the cinema. It's a hot summer day, and his nose is starting to sunburn. A wave of people pushes out through the theater doors, releasing a blast of cool air that John leans over to catch. Most of them are chatting about the film. John tries to tune them out – he wants to be surprised. A middle-aged woman comes to a halt on the pavement next to him, looks around, and loudly claps her hands. John blinks, startled, and a young boy who was leaning over the fresh cigarette stubs by the rubbish bin turns slowly toward her with a look of disbelief. "Clapping?" he says. "Really?"

She gestures for him to join her, and he stares, maintaining his distance. "You can't have forgotten my name. No one has ever forgotten my name before."

The boy looks an odd combination of impish and grim, and John randomly thinks: Rumplestiltskin.

"No more trash," the matron says sternly. "Or dead birds. Come here," she makes a stabbing gesture with her index finger, "and wait for the car."

The boy shuffles toward her, looking mildly fascinated at being treated like a terrier. John loses track of them for a minute or two as he buys his own ticket. When he glances back, they're still arguing.

"I'll be telling your mother that you insisted on sitting in the lobby through the whole film. Our tickets were a waste of money."

"Real people are more interesting to watch than fake adventures."

"Well, rest assured, after today no one from our agency will ever take you on an outing again. I'm putting a note in your file."

A black car pulls up, and she reaches for the passenger-side handle.

"Excellent," the boy says quietly, and climbs in.

22 minutes, 48 seconds (I don't say anything)

This is the last time he's riding the tube, Sherlock decides. It only confirms his worst suspicions about humanity. The idiot next to him has filled in every single line of his crossword related to meaningless pop culture fads, but he's still puzzling over #34 down. How can anyone in this day and age not know the technical definition of a scherzo?

Just before Sherlock's stop, the man lowers the paper with a defeated sigh, the last boxes still blank. He looks irritated with himself, and Sherlock takes comfort in that. He has to go through life being constantly annoyed by other people's ignorance; it's nice to think that ignorant people might occasionally feel the sting, too.

Sherlock could tell him the answer, of course. This never occurs to him.

30 seconds (play the violin when I'm thinking)

The notes are atonal and jarring, almost frantic. The poor bloke's never going to make any money this way, but he sounds like John feels this morning. John drops a pound note into the open – empty – violin case on the pavement and moves on. Just as he turns the corner, a pure chord strikes like lightning. It's bright and powerful, but John's running late and he can't slow down to hear where the song turns next.

2 minutes, 12 seconds (use mine)

Sherlock dashes into the lift. It's crowded, which would normally annoy him. But today's project is to break into the corporate suite on the 14th floor, and he's currently lacking appropriate tools, so he crams himself into the ideal pick-pocketing environment. There's a weathered, compact little bloke towards the back who seems the type to carry a pocketknife. He's staring at the ceiling with lines of exhaustion under his eyes – first year med student, rugby player, problems at home Sherlock deduces absently. With apologetic smiles and incongruously ruthless elbows Sherlock jostles his way over. It's the work of a moment to swipe the knife from that left-hand jacket pocket, and Sherlock hops out at the next floor.

It's a much better tool than he was expecting. With most multiplex knives these days the corkscrews are the only bits that get any use and the blades are cheap and flimsy. This beauty was solidly made half a century ago, and it's been through a war. An inscription – H.W. – is engraved along the handle, though the gilt has long since worn away. It serves admirably for burgling purposes and makes a pleasant jingle as the door bolt slips. While Sherlock examines the obvious, if damning, stains in the upper corner of the suite's storage closet, he entertains himself by reconstructing the history and habits of the knife's two previous owners. He even toys with the idea of tracking down the bloke from the lift and returning his property, partly because he hadn't meant to steal an heirloom, but mostly to see how many deductions he's gotten right.

It's rather a pity that, when the suspect bursts in five minutes later, the knife winds up flying out the window.

10 minutes, 23 seconds (it wasn't a difficult leap)

John's pretty sure the Y2K hype is ridiculous but kind of hopes it isn't. Every generation seems to get its own defining event, like it or not, and electronic mayhem would be a harmless kind of crisis to bond over. The "where were you when…" questions would be friendly and the memories warm, like the moon landing had been for his parents.

So just in case he's ever asked, he decides to get out of the pub – Harry's doing just fine on her own – and pick a nice spot to stand at the stroke of midnight. He winds up out on a bridge, though not by the Thames, as he wants to avoid the fireworks. The streets are swarming, the whole city awake.

"Got a light?"

John doesn't smoke, but he does have a packet of matches in his pocket with Violet's number scribbled on the back. He passes it to the tall, skinny stranger who's stopped to lean against the railing. With a nod of thanks, the man lights up and passes the matchbook back.

They stand at a comfortable distance, watching the water reflect the city lights. A huge cheer goes up as the clock strikes twelve. And just like that, the times have changed.

4 minutes, 16 seconds (Afghanistan or Iraq)

Sherlock doesn't spend as much time in graveyards as one might expect. If he needs something from a corpse he normally obtains it before burial; sometimes he even asks permission first. But a peculiar coffin has become central to his latest case – it's ill-proportioned, far too deep – so Sherlock sets up camp at the gravesite and waits for the mourners to arrive. Once they do, there will be trouble.

The groundskeeper is busy wrapping up a sale, standing with a young man by one of the shady plots under a beech tree. They shake on it, and Sherlock catches the end of their conversation.

"I hope you won't need it for a good long while, son," the groundskeeper says.

"I'm with you, there," the man smiles. "Thanks."

Sherlock wastes a few seconds trying to diagnose the man's illness from a distance before realizing he's not actually sick. He's military, that one, and about to be deployed, which makes the choice of this burial plot quite impractical. Sherlock cannot see the value in shipping mortal remains over thousands of miles for the sake of pure sentiment.

With a definite, settled nod the man turns and walks out the front gate. Frowning, Sherlock looks again at the green tree, the black earth under its shadow, and tries to see how it has given satisfaction. If the man dies, it will be in a desert. What use will beeches and shade be to him then?

The desert won't get the last of him, though. There is that.

Perhaps he simply likes to have the last word.