After Zoom's attack, Barry discovers a lot about himself.

And the Speed Force.

It's essential to understand one thing about it: it is not a passive medium.

It's responsive. When Barry runs, he can feel the difference between repression and ecstasy. Don't run angry, Cisco once cautioned him. He meant not to chase after a meta-human – in that case, Tony – and Barry doesn't confuse it, but he still has a compelling point.

If you run angry, you run blind.

Tapping into the Speed Force seems impossible when his vision is so occluded by rage he can barely see straight. He can't feel the subtle undercurrent, can't surrender to it, because he needs to reach his top speed now and patience is essential in catapulting above supersonic speeds. He could actually drop dead before he broke a thousand miles an hour from the sheer stress on his heart and lungs without the help of the Speed Force.

Luckily, his body is still an active voice in how fast he runs. When he runs angry, he doesn't see straight and he doesn't run fast. He's so focused on the end, the goal, that he abuses his power, trying to chase speed up a ladder when it's only those supersonic bounds that will help him unlock speed, so he rarely climbs above five hundred miles an hour, slow even for him.

He runs angry a lot. Chasing after the Reverse-Flash, always close on his heels but nowhere near his level; chasing after his own insomnia, hoping to tire himself out before sunrise from sheer raw exertion; chasing after the way he can't save all of them, how sometimes people die on his watch and how he needs to push himself harder to ensure it doesn't happen again.

Nine times out of ten, he does get hurt, but it's a satisfying pain, like sinking his fists into a punching bag too hard. It's the moment that breaks the endless cycle of run-faster-run-faster-run-faster. In the end he's hunched over and breathless and trying to think of a good excuse for Caitlin regarding the broken wrist he's now nursing, anything other than I needed to feel it, I needed to feel something other than hate.

(In the end, he can't, so he walks into Star Labs, puts his own belt between his teeth, and sets it himself.)

He's careful to run off hours, late at night, and Cisco and Caitlin notice, they have to, but when he walks in with a bright smile and a stack of coffees, what can they say?

You need to stop running?

He almost laughs at the thought. A speedster without his speed isn't an ordinary person. A speedster without his speed is half the person he was before it. Speed is as much a part of Barry as his hands, his ears, his eyes.

He can't imagine a world without it.

Even so, in some strange way, he finds himself compelled by it. He catches himself watching Jay, the way he folds his arms and frowns, silently taking in the world. No matter how subtle Barry thinks he's being, Jay always catches him at it, giving him a single piercing stare that immediately sets Barry back on the task at hand. He isn't visibly weak, but there's a lack of vitality to him that wakes Barry up at night and forces him to outrun the nightmare.

He can't imagine what he would do if he lost his speed tomorrow. How he would tell Joe and Iris I can't be a hero anymore. Returning to the precinct as some throwaway kid without direction, without a future at the facilities he once called home, without two of the greatest friends he has because what can he possibly offer them that they didn't have before him?

Life would never go back to normal. Speed is normal. Everything else is compensatory.

He runs to remind himself that he can and the Speed Force encourages him, pushing him like a coach, harder, faster, longer, until he can feel something in him settle, some inner peace finally sweeping over him as he breathes in, out, slow, concentrated.

It's a chant, a mantra.

I won't lose my speed.

I won't lose my speed.

I won't lose my speed.

Even when Zoom snapped his back in half with a single devastating blow (and Barry wants to take a flame and raze the memory to the ground, wants to do the same for the phantom jolt of pain it sends up his spine), he could still feel it. There was never a moment when he thought I will never run again.

Even when Zoom stabbed him through the chest with their own speed-suppressing serum and Barry felt pain on a scale he'd never dared contemplate, he didn't feel the sweep of coldness that would mean he was losing his speed; something chained it to a wall hard and kept it out of reach, but it was never gone.

Even when Zoom held him high in the air, choking him on gravity and his own blood more than the iron hand around his throat, punctured a lung with a single well-placed stab, he could still feel the lightning under his skin, trying to heal him, to reach him, to smother him from the pain.

No, Zoom hadn't taken his speed away (even though Barry didn't doubt he would have, would have consumed it for the sheer sake of taking anything else away from him).

He had lost his speed once: Farooq took it from him. The loss felt like someone had ripped out his heart; he couldn't breathe, couldn't escape it, couldn't feel anything, the lightning was gone.

When Caitlin finally came up with a solution, he didn't even hesitate, knowing fully well how painful electrocution was.

Anything – anything – was better than that stillness, that coldness.

Watching Jay on the sidelines whenever they train, Barry can't help but feel a crushing sadness on his behalf, silently vowing, We're going to find a way to get your speed back.

Even when Jay turns his back on them and walks away, claiming some excuse that Barry sees through (he couldn't imagine watching another speedster run knowing he might never run again), he keeps it in his mind. We're going to find a way to get it back, Jay.

So he runs for himself, to get better, faster, stronger, and he runs for Jay, too, hoping to unlock something, anything in the Speed Force that will give him an answer.

He thinks lightning is the key and wonders if he has to use his own lightning trick on Jay to shock it back into his system, except if he's wrong he'll kill him, and even if it doesn't kill him it might not restore his speed, might cripple him.

Barry can't risk it yet, so he runs as hard as he can at training, pushing the boundaries of his capabilities every day – and he keeps telling Cisco to lay it on him, give him all he's got, but Cisco exercises restraint, only pushing his drones hard enough to chase him, not to overtake him.

Barry needs to be overtaken, has to be forced into a corner where he has to fight because it's the only way he's going to get stronger. No one succeeds by staying in their comfort zone: at some point, to hone his skills, he has to push too far. He has to work up to Zoom's level and that means more than speed: more concentration and will power and force. He can't hone those skills while Cisco runs him through the equivalent of laps around a field; he needs to be knocked over and forced to get back up, he needs to learn to fight under extraordinary conditions, because he will not get a third chance against Zoom.

Barry either brings Zoom down or he dies. Simple as that.

Knowing that every time he runs he's working towards that aim, Barry pushes himself: he runs at night, hard, learns to run with cracked ribs and monster headaches because he can't exclude the possibility that he'll be fighting under those circumstances when up against Zoom. He learns to run uphill and downhill, learns to run and make sharper and sharper turns (and acquires more and more blunt impact injuries as a result; luckily, he heals fast), learns to run and hit a moving target without breaking his hand.

Every training session, he's stronger than he was the day before. Cisco and Caitlin pick up on it; they look at him and he sees the way they can tell he's been training himself. No amount of drone-runs could enhance his skills so quickly; no amount of coaching could explain how he's already demonstrating new tactics they hadn't taught him, perfected in their absence.

He's getting stronger, a lot stronger, fast.

Like an echo, though, he hears Dr. Wells' voice: He hasn't reached his full potential.

And so, just when he feels like he's going to hit a wall he says to hell with it and pushes harder.

It's a cool anger, an anger he learns to suppress, control, and he thinks he can't trick the energy under his skin, but he can tap into it, grab it even if it takes significantly more effort to do so, and he can make himself run faster, and longer, and harder.

And in the moments when he's gasping for breath, lying on the ground and struggling to get back up again, he sees Caitlin and Cisco and Iris and Joe and his dad, imagines what would happen to them if Zoom got a hold of them, and he finds the strength to push himself upright in the fraction of a second before the drone shoots the place he was lying. He takes off at a sprint, feeling the rage hot under his skin because you are not taking them away from me.

He thinks of Eddie and Ronnie, too, of all the people he wasn't fast enough to save, and he doesn't actively think training's over when they get a police call, he just pours himself into capturing criminals and saving bystanders, using it to fine-tune his focus under pressure, finding a balance between fast and precise and above all, careful.

If he slips, Zoom will kill him; if he even stumbles, Zoom will catch him, destroy him. He has to be at the absolute top of his game or he doesn't stand a chance.

Staring out over Central City, feeling the electricity crackling under his skin and wondering when angry became his new normal, he falls into a familiar crouch at the edge of the city.

Barry takes in a deep breath to calm the shaking in his limbs and surrenders himself to the feeling of electricity under his skin. He feels the surge of adrenaline that preludes a run and that's all he needs to feel a tidal wave of yes, of run, Barry, run.

Then he takes off.

When he runs, he tunes out the rest of the world. It's just him and the Speed Force, and he can feel it as surely as his own pulse, his own breath, and he doesn't capture it in his hands but inhales it in his lungs and feels it with every heartbeat, slowing, slowing, slowing.

Conversely, he is speeding up, crashing through speed barriers until he's running fast enough to obliterate most hard metals on impact.

He doesn't test the theory because the faster he runs, the harder it is to stop, and he feels a strange sense of calm overtaking him even as he pushes himself harder, harder, harder. Once his breathing ceases as time comes to a virtual standstill for him (and he does take a breath – just very, very slowly), he's locked in, aware of a universe without pain and there's something like ecstasy here, where suddenly he isn't running angry, he's running because it makes him feel powerful, and good, and above all, unstoppable.

He could be more powerful, more Zoom-like, except he wouldn't use it to terrorize people: he would use it to stop the Zooms of his world, of other worlds.

And if you ever became him, who would stop you? a voice reminds pointedly.

He thinks of Oliver automatically, even though he knows how absurd it is. As engaging as it is to pit his abilities against Oliver's in a fight, Barry knows Oliver would succumb virtually instantaneously if he fought him at the peak of his abilities. At higher speeds he can actually anticipate movement to a much finer precision in a way that he can already do at "slow speeds." He can see an entire fight playing out before either of them makes a move, and in his mind's eyes no matter what Oliver does Barry still meets him halfway before Oliver takes a single step and boom, he's on the ground, and it's over.

Zoom relies too much on his own speed to anticipate movement, doesn't case a location, and Barry knows how to, now, would know how to remove surprises, to anticipate their hidden locations, because no one could fight him on equal footing: they would have to bring him down to their level to have a chance. The only way to do that with a speedster who could run fast enough to stop his own heartbeat?

Surprise. Ambush.

Sudden death.

Barry tells himself, You are not Zoom.

But all he can think about when he runs this fast is Zoom.

When the suit finally crashes, its design only meant to hold up to so many extremes, it always comes as a cold shock, and he reels himself in, barely, as he canters to a halt: stop too fast and you'll shear off your own feet. He comes to a halt at the intersection of two streets, holding onto a light post for support as his limbs shake, breathing deeply, forcing himself to keep vibrating as people notice the red streak in their midst, begin to edge closer.

"It's the Flash," someone says, and that's all he catches before he takes off again, the flash of a flurry of cameras already dissolving as he outruns them.

Next thing he knows, he's on the roof of Jitters, chest heaving as he lies on his back staring at the stars, his own vision dappled with its stars, and the last thing he hears is, "Barry?" before everything – goes – quiet.

. o .

Barry hears them before he sees them.

Caitlin is saying, "That's not even remotely realistic," while Cisco shushes her, crunching on what sounds and smells like popcorn, and he's trying unsuccessfully to open his eyelids but they're so heavy, every limb is his body aches vaguely, like an overextended muscle. He groans and Caitlin says, "Barry?"

"Present," he grits out, pushing himself upright with painstaking slowness, blinking and rubbing his eyes. "What happened?"

"You passed out at Jitters," Cisco explains, munching on popcorn, and Barry's blinking because he can't see them right, everything's vaguely fuzzy and it's making his head pound, so he sinks back onto the gurney and closes his eyes.

He listens, and he can hear The Walking Dead in the background, listens as a rolling chair whooshes closer, and then feels a handcuff slip around his wrist, clinging lightly as it connects to the bed.

"You are on house arrest," Cisco announces, "until Caitlin says so."

"Cisco," Barry protests, already tugging lightly at the cuff, and he could get out of it, he knows he could, but the thought of moving makes his head pound. He opens his eyes to glare at them and they're still blurry, so he asks instead, "Why can't I see?"

"Eye strain," Caitlin explains, shining a light into his eyes before he can shut them, cringing. "It should pass soon."

He hears the unspoken you heal fast and sighs.

"My head hurts," he admits, and he doesn't know where the need to echo his pain out loud came from except he feels like he's been running from it for centuries, living in another time and place and leaving someone else to deal with Barry Allen.

Now he has to be Barry Allen again.

It isn't particularly desirable.

"That should pass, too," Caitlin offers, and then there's an ice pack over his forehead. "Does that help?"

"Mm," he says, and it does. There's still fire under his skin but it isn't acute, suffocating, and he's aware of how every twitch of his fingers or beat of his heart seems so real. Even the gentle pressure of a blanket seems sharp in his mind, and the way the air smells, the way his chest rises and falls with every breath, it's so real, and he doesn't know when reality became pain but it is.

"You had eight badly healed fractures," Caitlin says, and he opens his eyes to slits to look at her, vaguely aware of her presence a few feet away, before letting his eyes shut completely. "I reset them and they're healing well, but don't move too much."

Ah. That's why he's so sore.

She just broke eight bones in his body.

"How long have I been out?"

"Well," Cisco says, crunching on popcorn idly in the background as the TV murmurs in the background. "Iris called us about two hours ago to say you were at Jitters and we showed up to pick you up about twenty minutes after that. Then we called in reinforcements because you are tall, dude, and finally Joe got you down the stairs and into the van for us."

Great.

Iris, Joe, Cisco, and Caitlin.

It wouldn't even surprise him if they called his dad at this point.

He can feel the tears at the corners of his eyes and he will not cry, he will not cry, so he sucks in a shallow breath instead and says nothing.

Thankfully, Cisco's a good rambler, picking up on the fact that he doesn't want to talk and keeping up a running commentary on The Walking Dead while Caitlin settles into a seat near Cisco, already arguing about medical accuracy.

As he listens to them argue, Barry tolerates more and more details: the fact that it's after midnight, according to Cisco; his chest feels like a solid swath of pain because at least four of the broken bones originate from his ribs and his right hand throbs because the remaining four are broken there; and the way he's still aware of the energy under his skin but it's less like pleasure and more like pain, a hangover, an overdose, something to gasp through and hope it ends soon.

When he finally dares to open his eyes again, he can make out details, even if they're fuzzy, like he isn't wearing glasses and needs them. He pushes himself upright slowly and sees Cisco draped over his chair, snoring impressively, while Caitlin reads on her tablet, TV finally silenced in the background.

He thinks about asking why they're still there, why they won't just let him go, he's fine, even if he feels like someone shook him hard and broke something, it'll fix itself, it'll be fine, but sleep is subtle and persuasive, dragging him under before he can form a single word.

. o .

Barry feels a warm hand squeeze his own lightly, and Iris is there, and he can tell it's her before he even opens his eyes, savoring the moment of peace – of silence – before he forces himself to look at her.

He feels better, and it's mid-morning, which is confusing, the light streaming in from the windows preluding Harrison and Jay's arrival.

He's glad – he doesn't know if he could tolerate them, too. Harrison's disapproval, Jay's disapproval, weigh heavily on his mind.

Speedsters have lost their minds to it.

He sits up slowly and she slides a hand around his back, helping him, and he's not tied down by anything so he stands, feeling otherworldly, like a messenger arriving in the wrong time, on the wrong Earth.

She keeps an arm around his waist, supporting him, letting him come to terms with his own physicality, before he draws in a deep breath, feels the lightness in his chest again, the ease with which he breathes, and it's almost dizzying. He's felt the crush of speed for so long he almost doesn't remember how thick and rich air is at sea level and not the stratosphere.

Then she hugs him, tucking her arms under his shoulders, and he rests his head on her shoulder, feels her warmth, her solidarity.

When they let go, he half-thinks she's going to take him to Jitters or maybe the station, he should be at the station, but instead they angle towards the park.

They sit at the base of a tree, perpendicular, and she pulls out a book but she never quite lets go of him, their shoulders just touching, the lightest twitch of her breathing utterly, entrancingly calming.

He takes it all in, the grass under his hands, the way the trees susurrate with the wind, the blue sky overhead accentuating the normalcy of it all, and comes to a realization.

Doing nothing calmly is better than running angry.

Feeling more relaxed than he has in a long time, he rests a hand over hers on the space between them and gives it a light squeeze.

Thank you.

. o .

There's something else imperative to understanding the Speed Force.

It's ruled by emotions.

As Barry looks over the sunlit field in front of him, streaked with soft pink, purple, gold, he doesn't see Zoom.

He sees the world as it is: laughing over drinks, taking walks between shifts, tackling hugs that almost take him to the floor. He tastes coffee, smells Iris' perfume, feels the joy of returning home to them at the end of the day. He anticipates plowing his way through three feet of snow, laughing as he flees Cisco's retaliating snowballs, and creating a snowman army for Caitlin to exasperatedly fight her way through just to get in Star Labs. He can feel the rush of satisfaction as Oliver helps him to his feet after another round of mock fighting he almost won, admiration at the way Oliver can leap up walls without super speed, gratitude at the way Felicity held the door for him when Oliver tried to slam it in his face, let him into their lives when he could have said no.

He sees the beach, the ocean, at sunrise and feels the same indefinable thrill, and looking out over the field, stretching for miles and miles and miles, he grins.

You run hard for desperation, blind for vengeance.

And you run fast for fun.

As he takes off, he hears his own ecstatic shout as he runs and runs and runs, feeling grounded and exhilarated, like he's finally figured out how to run on an Earth that doesn't hold him down half as much as his own, letting him go, freeing him up to move as fast as he can, as fast as he dares.

For the first time in weeks, he doesn't think Zoom.

He thinks about himself, his world, what it means to be the Flash, to be Barry Allen.

At last, breathless but beaming, he comes to a halt in front of the station. "Sorry I'm late," he says brightly, letting himself be absorbed into his disorderly, wonderful life.

Barry isn't perfect, and he's never going to be the fastest or strongest or best speedster out there, but he has a life, and it matters, and he's going to fight for it.

And in the end – it won't be the Speed Force that stops Zoom.

It'll be Barry.

It'll be the Flash.

He grins at the thought, thinking of who he is, what he stands for, what he's become.

They're different, but ultimately, he is the Flash, and he can feel the Flash's mentality overtake his own, calming, steady, reliable.

As he turns back towards Central City, towards home, towards everything, he thinks: Let's do this.