Laughing, head tipped back parallel to the pavement, desperate gasps of too cold air that burn his lungs as he breathes. This is what it feels like to feel alive. This moment of desperate chases through London back streets, of warm hands to help pull over walls, of the familiar weight of the gun in his hand, of the slick feel of snow falling down the collar of his jacket.
This.
More than being shot at out in the searing heat of the desert. More than every kiss, every manufactured intimacy with girlfriends past. More than every moment of normalcy.
Sherlock is spinning round, analysing different exits, different routes their criminal might have taken, and John can do nothing but sag against the crumbling wall at his back and laugh, and wonder when his life turned into this.
Then Sherlock's hand is fisting in his jacket, grabbing hold of him and tugging him onwards and John almost falls as he starts to run again, righting himself by grabbing hold of Sherlock's coat in return. And isn't that every symbol of their relationship wrapped up into a gesture? Both desperately hanging onto the other for balance; for support, to feel needed and wanted and racing through dark streets on a constant thrilling high.
He can't imagine Sherlock doing this on his own. He can't imagine ever not being there.
John senses the stillness up ahead – some sixth sense that tells him something is wrong a fraction of a second before they get there, and he yanks on Sherlock's coat, pulling him back, stopping him from running straight into it in his stupid reckless way. Slides past him even as he pulls him back, ducking low and tackling the man hiding round the corner to the ground. He tries not to notice the wire in the man's hands, the wire that would have been at the perfect height to catch Sherlock in the throat, because it doesn't matter. He was there to stop it.
He will always be there to stop it.
The man's struggling in his grip and John punches him, once, twice, a third time because he catches sight of the wire out of the corner of his eye again and it fills him with the sort of rage he pretends he doesn't own. Anger at the thought that someone would try to hurt Sherlock – try to kill him. He brings the butt of his gun down hard on the man's temple and tries to remember how to breathe as he finally goes still beneath him.
Sherlock is already on the phone to Lestrad, and John gets up slowly, flexing his hand to try and ease the throbbing pain in his knuckles. Kicks the wire so it skitters away into the darkness.
"Are you alright?" Sherlock is there, plucking John's hand from his side and smoothing long cold fingers over the cuts on the knuckles. Smearing blood from John's skin to Sherlock's and John supresses the sudden urge to daub the blood on Sherlock's cheeks – to mark him as his own.
"I'm fine." And as Sherlock catches his eye everything in between their words is apparent.
I'm sorry.
Don't be.
You hit him for me. You saved me. Protected me.
I will always be there to protect you.
Sherlock's fingers tighten over John's for a moment before releasing them, and he is smiling – the reckless smile that would make John run out of a restaurant after him, that would make him chase over rooftops with him, that makes John fiercely glad to be alive.
Sirens in the distance and the snow is falling faster now, thicker, coating the alley around them in a messy sludge that is the closest London ever comes to snow. John shivers, the heat from the chase leaving his body as rapidly as it came, and he realises he is soaked through, snow dampening his clothes and chilling him to his core. Sherlock shifts back a step, watching him, head cocked as though John is another puzzle he is trying to solve and John wets his lips nervously, tongue sticking out briefly to catch the snow.
And then he's laughing because he hasn't done that since he was a child, and he sticks his tongue out again, catching thick wet snowflakes on his tongue and letting them melt. And Sherlock does it too and then they're both laughing from the sheer absurdity of being out in a snowstorm catching snowflakes and criminals and how it shouldn't feel as normal as it does.
He feels so, so alive.
Sirens and the flashing blue and red of the police, of Lestrad come to scold them because he doesn't know how to thank them, but it will be implied with the half shrug as he turns away back to the car – back to the man being handcuffed. The slight head tilt that says well done, thank you, I couldn't do it without you.
John can't imagine Sherlock being here and trying to exchange the bare minimum of civil words with Donovan without him. Can't imagine not being there to poke him in the ribs when he comes too close to rude for this time of night. Can't imagine not being there as the cars and the lights and the noise fade away and it is just the two of them again in a dark alley with the rapidly settling snow.
The alley is a mess of footprints and there are snowflakes caught in Sherlock's hair and eyelashes and John has to fist his hands inside his pockets to stop himself from reaching out to brush them away. And then Sherlock is turning back to him, coming back to John after the rush and bustle of being part of the action, curling back into the single unit of Sherlock and John again that makes John feel like he is home.
He is reaching out, a single finger that is practically the same colour as the snow around them, and John can't do anything but stare at it as Sherlock's finger touches his face. His eyes closing of their own volition, shut in the darkness of sensation where there is nothing but the soft hiss of the snow and the ragged edges of their breath and the warmth of Sherlock's finger pressed against his cheek. And then the warmth is gone and John opens his eyes to see the snowflake poised on the very tip of Sherlock's finger. Tiny, imperfect, held for a fraction of a second between the two of them like a white flag of surrender.
But then it is gone, melted by the warmth and Sherlock's turning away already, starting to head for home and barely sees as John shivers. Shivers from the cold and the want and need and the sensations he cannot even name running just beneath his skin.
Sherlock pauses, then lifts his hands and un-knots his scarf from his neck. Turning back, knotting it around John's own neck before he even has chance to acknowledge what is happening. For the barest moment as Sherlock finishes the knot, his fingers linger on the scarf and his eyes linger on John's and there is a flicker of –something. Some unnamed thing – understanding or acceptance or surrender.
And then his fingers are gone and his gaze is gone and John feels strangely bereft. But the scarf warms him and sends a different shiver through him as he silently follows Sherlock through the thickening snow towards home.