Sherlock is ten years old when he decides that hearts are ugly.
He is sixteen years old when he decides that hearts are useless.
He is twenty-two when he decides to have his heart removed.
He is twenty-three when he does it.
A doctor in Lambeth with a dingy back room slices open his chest and carefully, ever so carefully, plucks out his heart and places it to one side. A clockwork heart is implanted in its place; some parts silver, some copper, some gold, some tin. It ticks and whirrs and at the centre there is a tiny pendulum that oscillates to and fro, to and fro: caught and trapped and caged. He comes round after a number of hours, still on the operating table, the two halves of his chest stitched back together with thin black wire. He blinks to clear his bleary vision, turns his head to the right and sees his old, pink, fleshy heart in a large glass jar, labelled with his name.
Sherlock pickles it.
He pickles it and keeps it on a shelf in the kitchen of each flat he rents, perfectly preserved, an ugly reminder of what he used to be before taking measures to improve himself.
The work is all that matters. His clockwork heart enables him to have a ruthless efficiency in the cracking of cases, the solving of mysteries. He doesn’t get bogged down in emotion like everyone else, he doesn’t feel empathy or remorse or fear when someone dies or when he makes a mistake or when he throws himself across rooftops. His heart speeds up when he runs or physically exerts himself in some other way, of course it does: a quick, steady tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, but it does not seize or flutter or go anywhere it doesn’t belong, like his mouth, sitting on his tongue as his old heart used to when he was scared, or dropping to the pit of his stomach or his boots due to disappointment or sadness.
Mycroft is horrified when he finds out. Sherlock can see it written on his face in the places no-one else thinks to look: the corners of his mouth, the pinch of his huge, Holmesian nose.
‘You’ve pickled your heart,’ he says, ‘And you’re running on clockwork.’
‘Yes,’ Sherlock replies with a small, smug smile. ‘Clever, isn’t it?’ He can hear his heart: a loud tick tock, tick tock.
‘Woefully short-sighted,’ Mycroft replies with a smirk of his own after shaking his shock away. He checks his pocket watch and gets up, his hand curled round the handle of his umbrella. ‘Good evening, Sherlock,’ he says, and sees himself out.
There are complications, of course. Being largely unable to comprehend emotion occasionally leaves Sherlock at a loose end, and algorithms and equations will only get him so far in his understanding of motives, of emotional cause and effect. John Watson limps into the lab at St. Bart’s and after the usual rapid-fire deductions about the man’s character, profession and personal history, Sherlock performs a quick calculation in his head. How much pleasure will x bring me? he thinks, where x is sharing a flat with John Watson. Intensity, duration, certainty/uncertainty, propinquity/remoteness, fecundity, purity, extent: 7 variables measured on a scale of 1-10 that will give him his answer, rather than relying on gut feeling which doesn’t work anywhere near as well without that ugly bundle of veins and arteries that used to live in his chest.
Intensity - how intense will the pleasure be? Judging by John Watson’s background and the nature of Sherlock’s work, the potential for intensity of pleasure is high. 7.
Duration - how long will the pleasure last? Potentially until one or the other dies. 9.
Certainty - how likely or unlikely is it that pleasure will occur? As likely as it is unlikely, so: 5.
Propinquity/remoteness - how soon will the pleasure occur? It could begin tomorrow. 9.
Fecundity - the probability that the action will be followed by similar sensations: If the arrangement is agreeable, there should be no reason for the pleasure experienced not to continue. 8.
Purity - the probability that the action will not be followed by sensations of the opposite kind: impossible to calculate at the present time but with Sherlock and his clockwork heart things could very rapidly go downhill, thus: 2.
Extent - how many people will be affected by the action? If the arrangement makes Sherlock even more efficient due to having an assistant and not having to worry about trivial things such as food in the cupboards, then it will affect everyone Sherlock works with for the better. In that case, the action of living and working with John Watson scores 10.
The action scores 60 out of a possible 70 on the hedonic calculus; therefore the action is desirable.
He can hear his heart: a loud tick tock, tick tock.
The work is all that matters. Sherlock doesn’t understand John’s nightmares but he does understand that John’s nightmares make him less useful: he is tired, irritable, quick to snap at Sherlock and anyone else who is around the morning after his sleep has been disturbed by unpleasant memories - some of them real, most of them fabricated and made worse by his own brain, in cahoots with his ugly, pink heart and all of its emotions and feelings about things that can’t be changed now. Treacherous organs.
It only makes sense for Sherlock to do what he can to stop John's nightmares, or stop John being affected by them. On the third night in one week that he hears John's fevered, sleep-slurred yells, he runs up the stairs and climbs into bed with John, wrapping his long limbs around John's compact frame and holding him tightly. John does not wake and his shouts quiet down to soft cries, then mumbles, then nothing. Sherlock's clockwork heart sits in his chest, pressed to John's back, a heavy and loud tick tock, tick tock over John’s even breathing.
Sherlock leaves after holding John for an hour or so. He returns to the moth wings he had been examining on the kitchen table, the creatures stretched out and fixed to a corkboard, conquered with map pins. He idly wonders what their hearts are like and stays hovering over his experiment until morning when John comes down in search of his usual cup of tea to start the day.
'Did you get into bed with me last night?' John asks.
'You were having a nightmare,' Sherlock replies, his eyes flicking up from the large, brown moth he is inspecting with a thick magnifying glass.
'Yes,' John says shortly, a flush appearing on his cheeks. Sherlock isn't sure why, though from what he can remember, he makes a guess at embarrassment. 'And?'
'You slept better with me there. You’re better rested this morning after a good night’s sleep and as a result you’re more likely to be useful to me should a case come up. Ergo, I’ll continue to do it as it appears to be mutually beneficial, unless you’d rather I didn’t,’ Sherlock says, his cat’s eyes flicking up to John’s face again.
‘No, it’s... I don’t mind,’ John mutters as he takes the kettle off its stand and fills it.
‘There we are, then,’ Sherlock murmurs, squinting at the furry body of one of his pinned victims. ‘Aha!’
When James Moriarty tells Sherlock that he is going to burn the heart out of him, Sherlock has to fight not to laugh. If it weren’t for John - useful, necessary John - being strapped to enough semtex to take down the entire building, he would have done. Oh, he’d have laughed. Burning his heart out, what a ridiculous notion. He could try, but he’d fail. The gold and silver and tin and copper creation that keeps Sherlock running, keeps him ticking over would have to encounter something very extraordinary indeed to be affected in the slightest.
On the fifteenth time of Sherlock climbing into bed with John, John’s nightmare is awful enough to wake him and wake he does, kicking and thrashing and shouting. Sherlock grabs hold of his wrists and climbs on top of him and pins him into the mattress, staring hard at John because he isn’t sure of what to say. He can hear his heart: a loud tick tock, tick tock.
John draws in several deep, shuddering breaths. His temples are damp with sweat and his eyes are unfocused as he shakes free of Sherlock’s grip and grabs Sherlock by his curls and pulls him down and kisses him and kisses him and kisses him.
Sherlock thinks this: Intensity 10, duration 10, certainty/uncertainty 10, propinquity/remoteness 10, fecundity 8, purity 2, extent 2, and fifty-two out of seventy is acceptable despite the inevitable negative repercussions five minutes two weeks seven years down the line when John finds out, so he kisses back, slides his hands into John’s damp hair, pushes his hips down and bites and sucks and takes.
The complex mechanism of his heart whirrs and clicks; springs and gears and cogs and wheels turning and working at a rapid pace. He can hear it: a loud tick tock, tick tock, as well as the steady thump thump thump of John’s heart.
John comes undone underneath Sherlock, his hands holding Sherlock’s shoulders with an iron grip as he trembles and gasps Sherlock’s name. Sherlock reciprocates with a moan as he comes and collapses on top of John, finished.
‘Sherlock,’ John mumbles, rubbing his face against the top of Sherlock’s head, running his hands all over Sherlock’s still-clothed body. ‘Sherlock, that was...’
Sherlock frowns. He can hear his heart: a loud tick tock, tick tock. He can feel it, too: cold and big and hard and in that moment he longs for that fleshy, pink, ugly, god, so ugly mass of ventricles and veins and the vena cava and arteries and auricles and the aorta that sits pickled in a jar on a shelf in the kitchen to be back in his chest so he can feel something other than just finished, so that he can feel something.
He rests a hand on John’s hip and says nothing.
One day, he will tell John, or John will figure it out, or John will ask about the heart labelled with Sherlock’s name in the kitchen or Mycroft will deliberately let it slip because nothing that Mycroft does is not deliberate.
Until then, he takes from John all that he can, and he gives all that he wants.
They kiss and fuck and Sherlock tries to pretend that he can understand how John feels about him, he tries to pretend that he feels the same way.
He does try.
It’s only a matter of time until John finds out and Sherlock has the constant reminder of his heart: a loud tick tock, tick tock.
Tick tock, tick tock.