Author's note: Well, this is what happens when I have 5 other stories started - I go and write a sixth, completely unrelated one...

Anyway, this fic can be read and interpreted in two ways - for the purpose of not spoiling anything, I won't say how, but I wrote the explanation in the end note.

I'm pretty sure that it has been well-established by now that I am not among the owners of Sherlock, so I consider this disclaimed.

Enjoy your reading! :)

Direction, speed – they are reversible. Faster – slower, ahead – backwards. One can walk, then turn around, circling a 180 degrees and walk right back the way they came. Everything is a line which stretches in two directions, and for the most part, both of those directions are available to us. Except for time. Time only flows in one direction, and we are stranded in it, carried by currents we mostly never notice are whirling around us. No one can walk backwards along the timeline, and maybe that's for the best, because what if someone could? Only one person, being dragged back through the barricades of time. Where would they go? Or, better say, to when would they go? Most importantly who would they leave behind (or is it ahead)?

There is only one way to tell this story – the way it happened. This is not a story told from end to beginning, although it might seem so. No...Unfortunately, this is a story told in a plain, beginning-to-end chronological progression.

There is nothing extraordinary about the day it happens– no life-altering events, no case-solving breakthroughs. It is an ordinary day. It is the first worst day.

It is the day John's time starts to flow differently from Sherlock's. It is the day John's clock starts to run backwards.

In one moment both John's wrist-watch and the clock on the display of Sherlock's phone show noon. Sixty seconds later, the digits on Sherlock's phone switch to 12:01. John's watch shows 11:59.

"Huh. My watch is acting up. Better go and have it fixed tomorrow. Do you need anything from downtown?"

"No."

"Okay then."

The next day John is still wearing his watch, and it is still ticking backwards. Sherlock notices (of course he does) and wonders why the anticlockwise movements of the metal hands against the plastic backdrop make him anxious. Sherlock Holmes doesn't appreciate anxiety any more than he appreciates the said feeling being induced by an inanimate object. And yet, it's there, despite his best efforts to banish it.

When he snarls at John about not taking it to the watchmaker to have it fixed (or just getting a new one, really John), John's look of utter puzzlement makes Sherlock long for the clock-induced-anxiety (at least that anxiety had an easy remedy). As John stares at him, and contemplates Sherlock suggestion (order) as if it were the most novel thing in the world at that moment, Sherlock longs for that inexplicable, yet easily cured anguish. He longs for a watchmaker's tool box that he could use to fix it. He longs for a watchmaker that could fix this, because you can fix a broken watch, and he wants this to be just that – a broken meter of time. Even as he longs for all this, he already knows his wishing is in vain.

Longing is nothing but an unavailing escapade on his behalf, because, as John wonders what in heaven's name Sherlock is going on about, Sherlock realises John doesn't remember.

John's time is no longer running along with Sherlock's. John's time is running backwards – running away. John's time is running away from Sherlock's, and it's taking John with him, to the one place where Sherlock can't follow him.

But Sherlock Holmes is a stubborn man, horrible at taking orders and most certainly not very fond of being told what he can or cannot do. So, he decides this is just another battle of wits, and those he always comes out of victorious. He decides to refuse this realisation, refuse the broken wrist watch and its implications, along with the hated turmoil that trails behind them.

At 16:17, according to his phone (and 8:38, according to John's watch), Sherlock Holmes decides to fight time.

"Sherlock, have you seen my watch?"

"Yes."

"Care to share?"

"No."

"Sherlock."

"It's at the watchmaker's."

"And how did it get there?"

"I took it."

"Why?"

"..."

"Sherlock?"

"Experiment."

John's watch looks wrong in Sherlock's palm as he carries it from the repair shop three days later, but it ticks properly. 17:22, and counting. 1-2-3...34-35-36...58-59-60/0 – 17:23-

Time on the watch carries on as it is supposed to, taking Sherlock along with it, forward. Sherlock walks toward Baker Street, and he walks in stride with Time, feeling triumphant, for he thinks he might have just won that fight he decided to take upon himself. Little does he know that, while walking toward, he is still walking away (being carried away).

After he hands the watch to John, at 17:49, he pays it no more heed – that is, until, two hours later, he catches a glimpse of it on John wrist, just as John is passing him a cup of tea.

It shows 15:49.

Later that night, he sneaks into John's room and takes the watch off John's nightstand. He doesn't smash it against a wall or under his heel. He deconstructs it, cog by cog, until it is a corpse divested of all its connections, stripped to its basic parts.

Stop time. He is destroying time, because if time doesn't exist, then it cannot flow in either direction. If time doesn't exit, he and John can stay forever in this moment, in any moment – it doesn't really matter which moment it is, as long as it is stagnant and not John-less.

Only, he isn't really destroying Time, is he? He is simply destroying an instrument used to measure it, and the only thing he is stopping is the incessant ticking, completely insignificant for passing of Time.

Still, Sherlock Holmes is fighting Time, and he is doing it by any means available. He is fighting for John, and for himself, and for himself and John (himself with John), so in that moment he doesn't care if isn't stopping Time. He works at it until John's watch is just an impressive collection of gleaming fragments, laid bare and sorted categorically across the kitchen table.

He beats the watch that night, and it makes him feel just a little bit less helpless.

Still, he doesn't beat Time, but that's a war, and he is fighting it a battle at a time. There is a truth that keeps on being denied, but that's alright because he beat the watch, and a battle won in this on-going war is still a battle won, no matter how small.

Let me tell you the truth: Sherlock Holmes cannot beat Time.

"Sherlock, what the hell...? That watch was my dad's!"

"I told you, John, it was for an experiment."

"No. No, you haven't told me! You haven't told me anything about an experiment involving my watch! If I remember correctly, your latest experiment was the one dealing with the rate of disintegration of teeth in various acids and you've only started that one yesterday, so why did you have to do and destroy my watch?"

"..."

"Sherlock!"

"I got bored."

(Sherlock doesn't tell John he finished the teeth-in-acid experiment two days ago with John looking over his shoulder. He doesn't remind John that he was the one to help Sherlock write up the results.)

Two years – that's how long they have.

Actually, it's one year, eleven months and twenty-seven days, to be precise. Time is precise, units divided into subunits, repeatedly, so we must be, too. They have one year, eleven months and twenty-seven days worth of memories left. 727 days. Sherlock wonders if that's more than the number of teeth on the cogs he pulled out of John's watch.

(Would the cogs have been able to give them more time?)

For every clockwise movement of Sherlock's time, John's time takes a step in the opposite direction. If they had two clocks, one next to each other, and set them at 12:00, then Sherlock's would tick away, counting 12:01, 12:02... while John's would show 11:59, 11:58...The reversal is equal to the original progression. Time doesn't speed up, nor does it slow down. It's still mercilessly steadfast, fixed at a constant velocity. Only now, instead of being a vector with a magnitude and a direction, it's a sum of two vectors with opposite directions that cancel each other out. So, while Sherlock and John are still moving at the same pace (because John's second is still as long as Sherlock's, and John's day still has as many hours as Sherlock's), they are no longer moving in the same direction. Instead, they are moving away from each other, cancelling each other out.

Sherlock's having a crisis again, jumping around the flat in search of cigarettes. When John comes up the stairs, hands full of shopping bags (oh, how familiar, how usual that looks), Sherlock crowds his space, instantly, and pesters him for his secret pack. He knows nothing will come of it, he made John promise, again, two months ago – right after he deconstructed John's watch, and then ended up with a mild case of nicotine poisoning after chain-smoking for the greater part of the night. It didn't take much persuading, seeing as John was furious (worried) and very willing to agree to Sherlock's request, swearing to all that is right and holy Sherlock will never get a hold of another cigarette as long as he is around to see to it. So, Sherlock knows his request will not be answered with a nicotine hit. He knows it – counts on it.

Still, Sherlock is edgy and frustrated, and pestering John feels better than not pestering him, because that way at least they are both annoyed, and everyone knows misery loves company. Boredom mixed with the aches of withdrawal make him peevish and spiteful, so he decides to share the aches with John. He can't have his cigarettes, but he can have this, this shared annoyance, so he demands, with no real expectation of receiving that which is demanded.

When John simply walks up to the spare tea pot and takes out a white pack, handing it to Sherlock with a look that says 'No need to be so jumpy, you've just misplaced them', Sherlock wishes for the pain of the withdrawal. It feels like the sweetest ecstasy in comparison to this. John chuckles lightly at Sherlock's dumbstruck expression, and makes a small 'go on, then' motion, prompting Sherlock to draw out a thin white-and-yellow stick.

As John walks away, amused by his whimsical (and forgetful) flatmate, Sherlock feels like cigarette smoke. He is transient and dark and full of tar.

He never lights that cigarette. He never lights another cigarette, even long after John is no longer there to see to it.

John gets a new watch. This one runs backwards, as well, and Sherlock finds himself hypnotised into a sickening reverie by the antipode movements of its hands.

There are moments in which Sherlock is very acutely aware of the reversely ticking seconds. He can see them on John's wrist, little beats of a mechanical heart right above those of John's. But it's not really a heart beating there. Time doesn't have a heart. Time is utterly heartless. Time is a machine, and sometimes Sherlock wishes the same was true for him.

Sherlock can feel the hands of the heretic clock around his throat, squeezing, as if trying to stop his breath, reverse its flow until he suffocates. Sometimes he wonders whether he should let them, when the time comes.

(Oh, but that's the thing – Time is already here. It's been here all along and continues to be so. That's the problem.)

The day John forgets the fact that Sherlock doesn't have friends, that he 'only has one', Sherlock takes the emergency pack of cigarettes, abandoned long ago, and climbs to the roof. He doesn't smoke them. Instead, he piles them up and sets them on fire, watching the tar-laden smoke as it curls and occludes the stars that shift across the sky as the Earth turns. He blacks out the proof of passing of Time.

Sherlock wages a battle against John's new watch, and wins that one, too. He takes the new cogs, trapping them like prisoners of war. John gets a new watch – digital, this time. This one doesn't have hands, so Sherlock wonders why he can still feel them, tighter than ever, around his neck. He wonders how is he going to win this battle – this time, there are no cogs to be captured as hostages.

"She's alive, you know. I never told you, but recently she's been in the country again, and on the off-chance she might just reappear again, I believe you should know that she's alive."

"Who is?"

"The Woman."

"What woman?"

"...Irene Adler."

"Who is Irene Adler?"

Sherlock takes the battery out of John's digital wrist-watch. It's a new addition to his collection of obsolete war spoils. He despises them all, because they are a testimony to his failure.

The day John forgets the pool and the explosive-covered vest and 'people might talk' and 'people do little else', Sherlock sets a countdown on his phone, makes his Time run backwards, just like John's. When the alarm marks the end of the run, he starts a new one. And then another. And another.

Three days later, when the battery on his phone runs out and he is forced to check the time on the kitchen clock, he sees that his attempts at making Time move the way he wants were absolutely futile. His Time keeps on moving forward.

Sherlock beats every watch and clock he comes across, accruing cogs and batteries, defeated armies now at his mercy. He wins every battle, but still, he is losing the war.

The day John forgets Lestrade and Mrs. Hudson, Sherlock smashes every clock in Baker Street, including that in Mrs. Hudson's living room. It doesn't make him feel better – he can still feel the clock-hands around his neck, and he knows he is losing the war, no matter how many cogs and batteries there are, lying at his feet.

It all ends when John doesn't come home after surgery. In Sherlock Holmes' description, the word frantic has only ever been used in relation to his deductions or his passion for cases. When John doesn't come home that afternoon, it's a whole new kind of frantic that Sherlock turns into.

His mind is ticking, like those much hated wrist-watches, with the endless possibilities of what could have gone wrong.

Tick-tock-tick-tock- an enemy or an angry perpetrator they helped put away got their hands on John - tick-John- tick-tock- John is hurt or kidnapped or...tick-John-tick-John-John-John...

Hours later, when the sky has darkened and there is no Sun to be used for tracking of Time, Sherlock finds John trying to open the door to his old lodgings – the ones he lived in during that limbo period between two battlefields. He doesn't wonder about why John came here– he knows why, (and still, he pretends not to, just for a second – borrowed time).

John came home – the only place he now remembers as such.

"John..."

"Yes?"

"What are you doing? Come back - "

"I'm sorry...do I know you?"

"I..."

"Yes?"

"Nothing."

"Well...sorry to be rude, but I have to go and find my landlord. The bloody lock is acting up. So, urm...goodbye, I guess."

...

"Goodbye, John."

As John walks away, in search of his landlord, little does he know the man died a year ago – a year after John moved out of his army-provided flat and into 221B.

As Sherlock watches John go, he casts a glance at his phone, and then chucks the device away, into the nearest rubbish bin.

The clock on Sherlock's phone shows midnight. John's new wrist-watch shows midnight as well.

In the next moment, the digits on both gadgets change.

Both are now showing 00:01.

Time finally starts flowing in a single direction again, but Sherlock has lost his war and no longer checks the Time, so he doesn't see this and doesn't turn around.

John doesn't know he should care about any of it, so he doesn't see this and doesn't turn around.

And here we are – we've reached the end, which is also the start. We've travelled in two directions at the same time, and now we've come to the highest value on the timeline to ever be reached, the furthest point to which it has ever been travelled, while at the same time returning to 0, to the origin.

It is the last worst day of their life together and the first worst day of Sherlock's new-old life. Life without John. Life after John.

It's the first day of John's old-new life. Life without Sherlock. Life before Sherlock.

Is it the first worst day of John's new life? Maybe...but it's not as if he has any way of knowing this. Can you miss something you never knew you had? Can you miss that which never happened?

After that day, John stops forgetting, for a while. He doesn't forget anything else, for a long time. I wish I could say he never forgets anything ever again, but I can't, because after some time his watch starts ticking backwards again. After a while time gets bored of flowing in just one direction, again, and John starts forgetting again, so let's just settle for a long time.

However, there is a never here, should we insist on finding one. So, should we insist?

There is a never in this story - John never again recalls the things he had forgotten.

(At least, not that I know of...I guess, for a definite answer, you should ask Time)

Sherlock sometimes goes to see John.

Once he tries speaking to him, but it seems to upset John, and that makes Sherlock feel...It doesn't matter how, really. It makes him feel, when he spent such a long time trying not to, and that fact alone is enough for him to abandon any ideas about future attempts at contact.

From then on, Sherlock always watches John from afar, and mostly goes unnoticed, except for the times when John looks back. John looks at Sherlock the way one would at a memory that can't really be seen, a memory that isn't really there – looks through Sherlock, as if trying to remember what precisely it is he is supposed to be remembering. Sherlock never looks away first – it's always John who does that (because, really, what is the point of looking at something you're not really seeing, something that isn't really there?).

Sherlock looks at John and feels as if he is drowning in cigarette smoke and wrist-watch cogs and batteries and memories. It's the most exquisite pain.

John is Sherlock's nightmare of drowning.

There are days when John thinks he remembers a dream, a beautiful and exhilarating one. He can't remember what the dream was about, but the feeling tells him it was something akin to flying. John likes those days. They come randomly, but there appears to be a common denominator to them. It takes John time to figure out what it is, but eventually he notices that this feeling coincides with the appearance of a man. A tall man, in a dark coat with an upturned collar. A stranger. John thinks it strange and tries to remember whether he has ever seen the man before. He runs through his memories – Uni, army time, even Afghanistan – but always comes up empty. No, he never met the man. It doesn't matter, it's probably a coincidence, anyway. John shrugs it off.

John looks at the stranger and feels happy in that moment, and knows that whatever the dream was about, it must have been lovely.

Sherlock is John's dream of flying.

What would you do, if the one person you loved the most went there where you couldn't follow, while at the same time being right in front of you?

Would you fight Time for them? What a stupid question. Of course, you would.

You would lose.

What would you do if you never met the person you loved the most? What a stupid question. You wouldn't do anything, because you wouldn't know.

I guess you would be lucky, that way.

Remember the truth I told you? Sherlock Holmes cannot beat Time.

In the end he doesn't, but he doesn't surrender himself to Time's mercy.

In the end, Sherlock Holmes wins the final battle in a lost war, because (unlike John) Sherlock doesn't depend on Time to dispose of his memories. He is perfectly capable of doing so himself.

In the end, Sherlock Holmes refuses to allow Time to treat him the way he has treated John's wrist-watches. He doesn't allow Time to take him apart, cog by cog, until he is just a shiny collection of useless pieces that were once a stunning mechanism. He is no prisoner of war.

Time may have John's memories, but Sherlock is determined it cannot have his – even if that means that neither can he.

(You can't lose that which you don't have.)

The day their Times started to flow in opposite directions is the first thing to go.

John's watches go next, along with the cogs and the cigarettes.

Sherlock deletes the way John takes his tea.

He deletes the fear that smells like pool water, and the number of hours John needs to sleep in order not to be agitated.

He deletes John's blog, and 1895 on the counter, and clock batteries.

He works through the memories, systematically, just the same as Time has worked through John's. Under some other circumstances, he might be able to appreciate the irony of that.

In the end, at the very end of Their Time, Sherlock Holmes deletes John Watson.

Two men sometimes dream a similar dream.

One dreams of drowning in a sea of cigarette smoke and wrist-watch cogs and batteries. The other dreams of flying. They never meet in that dream because there is a line between the sea and the sky, which cannot be breached.

Yet, the drowning man sometimes thinks he sees a silhouette among the cogs, veiled by miles of smoke. It appears to be carrying shopping bags. For some elusive reason, he feels as if he should know who that is.

The flying man sometimes thinks he sees a dark shape against a cloud. It appears to be wearing a coat with an up-turned collar. For some elusive reason, he feels as if he should know who that is.

Do they ever recognize each other? I don't know.

Ask Time.

Ok, so - when I started writing this, I intended it to be just a fic with fantastic elements regarding time, but as it unfurled, I realised it can easily be read as an analogy for demetia or Alzheimer's.

I leave it to you to decide which way you want to interpert it :)

Thank you for reading!