Author's Note: I don't own Castle.

"You sure you want to do this?" Esposito said, pausing outside the door of the tiny Flatiron district boxing gym he worked out at. He looked at his partner, really looked. Somehow there was a line in the code of partners that made what he'd done, losing his temper and hauling off and punching Ryan, a negligible offense as long as he was buying the beer afterwards. A thing that didn't count because of the reasons why.

It was almost too much forgiveness, come by too easy. There was no missing the bruising and puffiness on Ryan's face. It might have blended in with tiredness and shock and grief, dark circles and weary eyes, but it was there. There was no missing the evidence that a man who should know better, who should be disciplined better, had lost his shit in a way that should never have been taken out on his partner. The things Javier had been trained to do with his hands, the chances he should never take.

So he did owe it to Ryan to be here, in the early morning when the City that Never Sleeps was yawning, dozing, and pulling the covers over its head after another wild night. He owed it to his partner, his brother, to let him get a few shots in, to work off some steam with him, on this day of all days.

"Am I sure?" Ryan said, slight annoyance creasing his face. "What, you think I can't handle you? Yeah right. You think you learned anything in the special forces that I didn't learn in Catholic school? Bring it."

Esposito shrugged and keyed in the pin to get into the building. There were privileges to being a clean cop, being known around the neighborhood. The gym's owner, retired Army and a former boxer, liked having him around.

Ryan followed his partner down the narrow stairs to the basement gym, past a locker room consisting of one bench, a towel rack, and two open shower stalls. They were both already dressed to hit the ring. Esposito had a bag full of gear slung over his shoulder that he carried through to the small room that was dominated by the square form of the ring.

"Here." he said, unzipping the bag and tossing basic headgear and gloves to Ryan. "You better have your own mouthguard with you."

Ryan pulled the case with his mouthguard out of his pocket and held it up. The two didn't say much as they stripped off sweatshirts, stretched lightly and put on gear.

"You wanna wrap your hands?" Esposito asked before he put his gloves on.

"Nah, I'm good." Ryan was fidgeting with the unfamiliar head-gear, a leather cage that left most of his face free but protected his brain and jaw. The hefty face protector was built out to be much more defensive than the lightweight helmets worn by competitive boxers. He'd worn something like it before at the Academy and during refresher classes on personal defense, but it wasn't something he wore that often.

"You sure we need these?" Ryan said, holding up the bulky boxing gloves. "You don't have any bag gloves?"

"Bro." Esposito said, shaking his head. "We've got nothing to prove here. Just gotta blow off some steam. And Beckett will kill us if either of gets messed up before..." he trailed off.

"We do this the right way." Esposito concluded.

Neither of them wanted to talk about later, about the other familiar but now-seldom worn garments they'd be putting on. The formal blues, the polished dress shoes.

Ryan made a begrudging grunt of acquiescence. "Fine, we'll do it your way. Can we get in the ring now?"

"Let's do it."

Esposito climbed through the ropes with the ease of a man entering familiar territory. He held the ropes for Ryan. There was no-one to ring a bell for the start of the round or to lay down the law. The two men just clumsily shoved in their mouthguards, touched gloves, and got to swinging.

Esposito was holding back. Where had this control been when he needed it, when he let loose his fury and physical power, the advantage of size and training on his partner? Not that Kevin Ryan couldn't take care of himself, he'd thrown down right there and then, challenged Esposito, shoved him, pushed back, taunted him to go ahead and hit him again.

The thought of that adrenaline and betrayal filled rage, the thought of holding his partner against that brick wall and nearly swinging again, that just sickened Esposito to the point that now he was dancing around, throwing haymakers that were easily deflected. Yeah, he'd agreed to spar, burn off some of the anger, confusion, burn off some of the pain, but how was he supposed to throw a punch in earnest?

"That all you got?" Ryan taunted, the words muffled heavy and spit-laden by the mouthguard. He darted in with a jab that made it past Esposito's distracted guard, glancing off his ribs.

"That all you're going to bring?" Ryan slurred.

There was a light in Ryan's eyes that was as ugly as the one Esposito had seen in the mirror that morning. They both felt it. They both felt the jarring sense that nothing was right or clean any more. Nothing was as simple as trust.

Esposito shook his hands out quickly then put them back up in front of his face. The two men moved around each other, watching each other's footwork, appraising. The small room was already getting sticky with heat, closed off and claustrophobic, the one fluorescent light overhead flickering and throwing long shadows off them.

Ryan swung out suddenly, feinting with his left hand, a little jab easily blocked, following through hard with a right that would have been messy if it'd connected with Esposito's nose the way he intended.

"Fuck, bro." Esposito spat around his mouthguard as he bobbed under the punch and came up with an uppercut to the bottom of Ryan's face protector in response. He held back, still, pushing down the anger at Ryan's reckless punch. Beckett really would kill them if they disrespected Montgomery that way. No matter what the Captain had been or what he'd done. He deserved to be honored as a hero, in her eyes.

You had to be able to trust your partner. That was basic. He'd been partnered with Ryan six years but they were blood just the same as if he'd grown up in the Bronx with Ryan's sprawling family. Not everyone got to trust their superior. Some men and women played politics, didn't play it in a way that kept you safe. Esposito knew that all along the line, from when he'd been a grunt in boot camp to when he signed on at the Five-Four, right up until he transferred into Homicide at the Twelfth. Roy Montgomery was the straightest of the straight shooters, a man who put his officers first.

Until he wasn't.

Ryan's light eyes turned dangerous as Esposito's fist clipped him under the chin, rocking his head back. He chewed on his mouthguard and ducked under Esposito's follow-up swing, using his smaller stature and speed to get in under Esposito's guard. He threw tight punches to Esposito's abdomen, one-two, one two, ignoring how unguarded his head was.

Esposito should have been throwing punches right at Ryan's thick head to get him to lay off. Ryan was obviously trying to get him to drop his guard further, trying to get up in his face, trying to make him lose control again, the way he'd lost it at Ryan for being the first to believe, the first to understand that Roy Montgomery wasn't the man they'd thought he was.

Jesus, was this any way to grieve? He shoved Ryan's shoulders, pushing him back. The part of him that was trained to take a man down, neutralize him at all costs, was screaming 'threat' and suggesting that a couple of knees to the groin and an elbow to the back of the neck would get this over with. That was not a useful train of thought, and Esposito banked that, focusing, concentrating.

Did he owe it to Ryan to lose control? To give him what he wanted, the primal satisfaction of a hard scrabble to take each other down, no-holds-barred? If he did, if that was his penance, he couldn't do it.

Ryan landed a punch on Esposito's solar plexus. With an 'oof', Esposito bent, shoving Ryan away from him hard. That was going to bruise, even with the gloves on. He got his hands back up and stepped backwards away from Ryan, resetting his stance, breathing heavily. Sweat beaded down his close-cropped head, down the back of his neck, tickling his back. He ignored it, focused only on his partner and the shimmering emotions in the air between them.

Ryan wanted this to go hard, wanted to feel something, wanted an outlet? Well, he was going to get it.

Ryan was breathing heavily, too. Esposito figured there was still a ways to go before they were done with this. There was plenty of time before they'd have to shower and go home to the dreadful ritual of putting on the uniform.

Esposito stepped it up, speeding up his movement, swinging higher and harder, making Ryan work to block every single blow. Ryan barely had time to throw light jabs back at Esposito's head.

It couldn't have been more than half a minute before Esposito got one through Ryan's defense, landing a hook to the left side of Ryan's head. Ryan stepped away from it, shaking his head and throwing his hands back up clumsily. Esposito took advantage and threw a low blow to the body. Ryan's anger was making him a sloppy fighter, careless.

Ryan made a sound that was almost a howl, a barbaric yawp, baring his teeth mouthguard and all and rushing at Esposito in a way that left him wide open.

"Enough!" Esposito said. That wasn't sparring, that was a man in pain. He grappled with Ryan, gloves making it hard to grab his shoulders, and the memory of the alley, of ending up with his partner shoved against the wall making him sick at what he had to do.

"Enough." he growled past the mouthguard. He took Ryan down to the mat in a practiced move, pressing him down with his weight.

Ryan was panting now, sweat mixing with salt from his eyes. No, he wasn't crying, exactly. He'd just got to let this out, get this out.

Esposito spat out his mouthguard.

"I know, I know." he said. "Yeah, I know."

"He lied, he fucking lied to all of us." Ryan mumbled. Esposito let him sit up, took his gloves off and helped Ryan get his gloves and helmet off.

"Yeah. He did. I didn't want to believe it, but he did."

"He would've used us to shoot Lockwood."

"Lockwood needed putting down. He would have taken out Beckett."

"Yeah, but he used us." Ryan said, agony in his eyes. "I would've shot Lockwood like he said."

"You wouldn't." Esposito said, letting his partner lean on him. "Not unless it was necessary force. You'd want to, but you wouldn't."

"You can't know that."

"Sure I can. I know you, man."

Ryan wiped his arm across his face, sniffing.

Esposito looked away, taking deep breaths that made him feel every punch Ryan had landed on him, glad they hadn't come around to talking about what he'd have done, whether he'd have done as Montgomery said.

He didn't know the answer. To protect Beckett, one of their own, would he have stepped across that line? If they'd got to Hal Lockwood, found him, if he'd had the choice between arresting the escaped murderer or shooting him down like a rabid animal, what would he have done? Would he have done it, shot Lockwood, because Roy Montgomery said those words? Because he trusted and respected that man?

He didn't want Kevin Ryan thinking less of him, no matter which way the answer went.