Disclaimer: I do not own any part of Castle nor any of the characters.

Well I got this idea running through my head as I read Eliza C.'s story and it needed to get out. Slightly AU and I made an adjustment to the character of Castle that may or not be real, but is still very plausible. To get an idea of the action scenes some things to youtube that would help would be "Metal Gear Solid 4 HD BR" select the first video and watch about 1:20-2:00 of the video. Now imagine only one person knows how to fight like that, would make it much more uneven of a fight. I basically envision Castle's Derek Storm to fight like the Metal Gear Solid snakes in games 3 and 4. CQC combat with a knife and pistol. Just youtube some more of it if you want more examples. I hope everyone enjoys this is a one-shot that I have not had betaed but I still hope is up to snuff. Anyway enjoy and if you have any questions ask in a review or PM me!

Castle's CQC

The team had been on a gruelingly difficult case all week and had recently hit a dead end which caused tensions to run a bit high. Beckett having to work off some frustrations had gone to the gym to meet with Detective Tom Demming to blow off some steam. Meanwhile Esposito and Ryan watched as Castle had himself firmly planted in front of the murder board.

"Dude, how long do you think it is going to take Castle to do something stupid about Beckett?" Ryan asked Esposito, confident Castle couldn't hear them at their desks.

"Seriously? I am surprised she hasn't noticed his comments all ready. Our boy is jealous about her and Demming, no doubt. I mean I doubt he is thinking about the board knowing what Beckett is doing upstairs," Esposito bantered back.

"Twenty says Beckett snaps at him before this case if over," Ryan offered.

"Double that she lays him out," Esposito countered right back.

Thinking it over Ryan didn't see any harm, besides they could always have more side pools if he lost. "Deal," he said shaking Esposito's hand.

Suddenly Castle shot up from his spot at the board moving closer to examine some notes. Ryan and Esposito looked at one another, they knew that look, Castle was on to something.

"Hey guys," Castle called. "How long is the scene of the murder out of the way for the wife on her way home?"

Ryan slightly confused, but still trusting Castle looked it up. "About five minutes why?" he asked.

"Our wife's Alibi puts her getting home to relieve the nanny fifteen minutes later than normal. She claimed traffic, but did we ever search her car?" Castle reasoned out.

Shaking their heads Ryan and Esposito brought up their notes realizing Castle was on to something. "Better get Beckett," Esposito said grabbing his coat after confirming Castles theory.

The three of them moved up the stairs and through the halls leading towards the precinct's gym. Nearing the doors that held the sparring mats they could hear the grunts and groans of hand to hand combat taking place. Ryan and Esposito looked at each other and then to Castle. Both were eager to see how Castle was going to react to what he saw on the other side of the doors.

Opening the doors the three of them walking in on Beckett and Demming in the middle of a grapple on the ground, which also coincidently happened to put them in quite a promiscuous position. Glancing at Castle Esposito and Ryan noticed the tightening of his eyes and the slight clenching of his fists. Yep, Castle was not happy with what he was looking it. Glancing at each other the partners decided to antagonize more than diffuse the potential future situation.

"Yo Beckett we got something, but it can wait until your finish up. You don't mind us staying and picking up some pointers do you?" Esposito informed her while taking a seat on a bench against the wall.

Ryan just piled it on. "Yea it's no biggie we can wait until your done," he said joining Esposito on the bench, both sharing a grin.

Their grins increased even more at the look of shock that was on Castle's face as he looked between the two of them and the pair grappling on the floor. Knowing Castle wouldn't be able to keep his mouth shut Ryan and Esposito just stayed quiet, planning on waiting him out.

Dropping into a seat heavily next to the partners Castle was already showing signs of impatience. First it started with a slight twiddling of his thumbs, then a few minutes later he leaned forward, a few minutes after that he was wringing his hands, next came the bouncing of his knee. Yep, Castle was about to crack all right and it was sooo going to be worth it.

While Castle's impatience was growing Demming and Beckett meanwhile were engrossed in their fight. Tom had been getting into shape recently and he was giving Kate a run for her money. It wasn't helpful that Castle, sitting and watching her, was not something she was completely comfortable with. Still she knew she had to keep her head in the game as her and Tom moved through combinations, holds, and throws. Kate couldn't really keep the smile off her face, fighting was similar to flirting or foreplay for her and she loved it.

Ryan and Esposito, who were more intent with watching Castle than the match, had giant grins on their faces as Castle watched Beckett's smile. Both of them knew about his jealousy, and they just wanted to give him a push forward. Hell they already lost the pool, but it didn't mean they couldn't have fun.

Finally Castle seemed to reach his breaking point and broke his silence. "Detective Beckett we have new info on our killer. Would you mind wrapping up so we can catch our suspect?" Castle asked not able to keep a bit of bitterness out of his tone.

Tripping up Tom, Kate stopped to look at Castle still having that smile on her face. "I'm sure if Ryan and Esposito think it can wait then it can Castle. Just sit down and be quiet until I'm done," Kate said dismissing his sense of urgency.

"Kate seriously we don't have time for you to sit around and play while our potential killer could be making her escape," Castle pleaded trying to appeal to her cop side. Apparently it wasn't going to work.

Kate, her grin growing larger at Castle's words, decided to have some fun with him. "Ok Castle I'll tell you what if you can knock down either me or Tom then we will leave right away. Just once knock us down, but if you can't then we get to knock you around until you get some sense," Kate said knowing that he would back down from a physical confrontation.

Looking at the two of them Ryan and Esposito knew this was better than they ever hoped. Neither thought that Beckett would actually challenge Castle, and they knew that he was going to have a hard time getting out of it while saving face. Castle was a powder puff so to speak. Both knew he would have to back out somehow or get his butt whooped, either way the entire thing would be priceless. However, what the two of them did not expect was Castle's response.

Sighing Castle looked at her and Tom standing on the mat watching him with little grins. "I suppose someone is going to have to wipe those grins off your faces, and since dumb and dumber aren't helping I guess that person is going to have to be me," Castle said with a sense of resignation to the complete surprise of everyone in the room.

Surprise was an understatement, the entire room was shocked. Castle fight Beckett or Tom, there was no way this was going to end pretty for him. Didn't he know that both of them were police trained in hand to hand combat techniques? Tom and Kate looked at each other in surprise, but then after a minute shrugged and smiles went back on their faces. Each was a little curious to what the author was capable of, and wanted to show him that you do not mess with the NYPD. Ryan and Esposito had a different take on the entire matter.

Whispering to each other their side bets started. "Since Castle is going to get clobbered I will give you three to one. Twenty bucks every time he gets put on his ass sixty for every time he takes one of them down," Ryan said eager to make a great deal of change on the entire matter.

Esposito thinking it over must have had some faith in the writer. "Make it four to one and you got a deal," he said which caused the partners to shake hands before settling back to watch the action.

Castle meanwhile had removed his sports coat and his shoes and was walking onto the mat to join the two detectives who were a little eager to take him down. Sighing once more at the inevitability of the entire thing Castle asked, "What are the rules?"

"Not many. Keep shots away from the groins, don't go overboard, and if someone taps then you let them go right away. Not that you will be able to do any of those," Tom said his smiling growing even larger if that was possible.

"Don't worry we will go easy on you Castle until you get warmed up. I'll go first," Kate said her smile to getting bigger at the perfect excuse to toss around the annoying author with his consent.

Nodding his head Castle got into an ugly defensive stance and waved Kate towards him signaling he was ready to start. Kate nodding at his signal rushed forward going into a basic combination of punches and kicks that put Castle right on his back within seconds with a loud thump. Ryan seeing this laughed as he looked at Esposito groan.

"I thought our boy had some moves, this is going to cost me a butt ton of money," Esposito groaned out not happy about the prospect of paying Ryan so much.

For the next fifteen minutes Castle was tossed around the mat in turn by both Tom and Kate, only sometimes getting a hit in here or there, but for the most part just being dominated. At the end of fifteen minutes Kate and Tom were having competitions to see who could knock him off his feet faster as they laughed at Esposito's increasing disappointment in his pick.

"Yo Castle," Esposito called while Rick was once again pushing himself to his feet, "I don't know how you keep getting up so much man, but either stay down or get me some of my money back. Heck I owe Ryan around six hundred bucks, dude that isn't cool," Javier complained.

Looking at Esposito Castle nodded his head before standing to his full height in front of the two detectives who were waiting for his signal to continue. By this point each had a look of respect on their faces at Castle's ability to take a pounding and keep on going, but neither was impressed with his actual ability to fight.

Castle since the beginning of the fight had remained quiet only uttering groans and grunts as he was hit and tossed around. Now though he decided it was time to speak. "Does anyone know what items Derek Storm used when he had to infiltrate a house?" he asked completely going off topic.

Ryan and Kate appearing to be the only ones who actually were familiar with the character gave him puzzled looks. Kate was the one who spoke up, "Yea he carried an mk23 pistol with a flash light attachment and a knife. What does that have to do with anything?" Kate's statement sent Javier and Tom into looks of confusion to, apparently everyone was clueless to where Castle was going with this.

Castle nodded his head at her answer. "Very good Detective Beckett you must really be a fan," he said causing her to blush. "The reason I ask is because I always wanted to know if you think you could take him. Do you think you could take down Derek Storm?" Rick asked as he began to undo the buttons on his usual long sleeve button down.

"I don't know he is a fictional character that you made some superhuman fighting machine. But if he was real I think I wouldn't have a problem since no one fights like you had him fight in your books," Kate said still confused about his purpose for the question while confident in her abilities.

Finishing unbuttoning his shirt Castle took it off to reveal a tank top underneath. After removing his top everyone had to do a double take at what they saw. Castle, the childish author that loved to joke around, was not nearly as soft as they all thought. Muscles were clearly evident throughout his bare shoulders and arms as well as the hint of a six pack underneath his tank top. Most peculiar though was what was strapped to his right forearm. It appeared to be a thin knife sheath.

Castle began an explanation for the benefit of Javier and Tom who were not familiar with the character of Derek Storm. "Derek Storm was an ex-Delta Force operative who used a unique style of fighting called CQC or 'Close Quarter Combat.' Through his training he learned how to use in tandem a knife and a gun to most effectively take down his opponents as quickly as possible," Castle explained as he slowly began to stretch out his shoulders and arms.

"After being tossed around for fifteen minutes, and in an effort to win Esposito his money back, I was wondering if you would like to see if you had what it takes to beat Derek Storm. That challenge also applies to you Detective Demming," with that challenge a grin appeared on Castle's face for the first time since the beginning of the fight.

Castle's theatrics caused a round of laughter to come from the four detectives in the room. Here he was author of a book thinking he was actually a character from his own novel, it was too rich. Grimacing at their mockery Castle just continued to look on as they were overcome with fits of laughter.

Feeling slightly affronted at their lack of faith in him he upped the ante one more. "If you make me tap out once I will not make a single joke for the remainder of this case and the next four," normally Castle would ask for something in return, but right now wiping the laughter and smiles off those four faces would be reward enough for him.

Kate getting herself under control looked at Castle while wiping away a tear from laughter. "Ok Castle you got yourself a deal, but since you upped the ante I won't go easy on you," she said still with a big smile on her face at the ridiculousness of the author in front of her.

Nodding his head at her he put one foot forward settling into a defensive crouch once again. However, Castle's new stance had Esposito and Ryan lean forward studying him closer. Previously, Castle had shown no experience or training in his defensive stance, for the most part standing like some guy who had never fought before. This time however Rick had one foot slightly forward, balance on the balls of his feet, and both hands slightly open in front of his face. True neither had ever seen someone stand like that in a fight, but it still suggested Rick understood what he was doing. Shaking their heads at one another they both settled back, Ryan happy to win some more money while Esposito a bit upset that his pockets were going to be pillaged a bit more.

Kate not wanting to draw this out any longer quickly went on the offensive. Four quick steps put her in striking range and she launched with a right jab aiming for Castle's midsection. Instead of trying to avoid her, like he had earlier, Castle instead grabbed the outside of her forearm with his left hand while reaching and grasping the inside of her elbow with his right. Applying pressure with his right arm and twisting Rick quickly upset her balance and set Kate onto her back. Rick Castle, author and father, had in one move not only countered Kate's blow but also put her flat on her back.

Esposito realizing he just made eighty bucks back let out a whoop at his turn of good fortune. Kate now embarrassed quickly got to her feet and squared up against Castle. Moving back into range she unleashed a forward kick aiming for Castle's solar plexus. Castle, almost if he had choreographed it with her, blocked Kate's foot with his left hand as he stepped around and to the left of her kick hooking his right inside arm across her chest driving her to the ground while she was still balanced on one foot. Once again Castle had dropped Kate to the ground without any apparent trouble at all.

Kate lay stunned on the ground completely shocked at what had just happened for the second time. She had thrown Castle around for the past fifteen minutes and now here she was on her back twice in less than thirty seconds.

Tom seeing the trouble Kate was having moved in to try his hand at Castle. Being more conservative he threw a right hook. Castle whirling to face him put one hand up to block the incoming strike while putting his other hand on Tom's opposite shoulder. Using Tom's own momentum Castle spun while pushing and pulling on Tom's shoulder and arm slamming him into the mat. Ryan and Esposito were completely stunned, where did Castle learn these moves. Clearly they were not taught at the police academy or even for SWAT team members.

What followed the next minutes was a complete reversal from the first fifteen. Where Kate and Tom had been the ones tossing Castle to the floor almost effortlessly, now he was the one keeping his feet as they were tossed around. Again and again they would come at Rick, and again and again he would send them sprawling after using some advanced form of martial arts. Whereas Kate and Tom were using punches kicks and basic forms of grappling Castle rarely threw punches or kicks. Instead he would use their momentum against them using only elbows, knees, and forearms along with advanced holds. None of the detectives had seen some of the complicated holds or joint locks he would employ on them, which meant that had no way of knowing how to avoid or counter them. Clearly this was the CQC that Castle had been referring to when he mentioned Derek Storm, it smelt of military origins.

Esposito at a complete loss looked to Ryan for an explanation who gave up what he knew. "I thought he made it up in his books man I swear. I have never seen anyone fight like this before, especially against someone like Kate. Hell the dude hasn't even gone to the ground himself yet," Ryan claimed in complete surprise at the entire spectacle before them.

Kate and Tom getting up after both being repeatedly put into the ground stood next to each other. One thing they both understood was that there was no way they were going to be able to take on Castle separately, and working together was their only chance. Kate herself was completely shocked about the entire ordeal. Castle was her helpless shadow that she protected. This was the guy whose nose she grabbed, whose ear she tweaked, and who had to use the safe word 'Apples' when she picked on him. When the heck did he learn how to defend himself? This was like the time when she learned he knew how to shoot all over again. Castle lulled her into a false sense of security only to completely throw her off her game with his actual skill.

Kate and Tom nodded at each other as they began to circle Castle in opposite directions splitting his gaze between the two of them. Castle smirking at their ploy darted towards Tom before they could get on opposite sides of him. Kate not wanting to let him gain a large advantage was close behind him. Reaching Tom Castle performed a quick spin as he dropped towards the ground swinging his arm to catch the back of Tom's leg with his outstretched arm in an unorthodox trip. Castle rolling to his feet got up in time to receive a kick from Kate right in his chest sending him staggering back. Not wanting to lose her momentum Kate followed up with a flurry of combinations knowing that if she gave him any leeway she would end up on the ground again.

Castle for the first time since he had begun to actually try was on the defensive against Kate. Like quicksilver her hands and feet moved dipping and darting looking for and hitting openings where they appeared. Castle knowing he was going to be in trouble, since Tom was getting back to his feet, knew that he had to break her momentum and put her on the ground… fast. Catching her fist in one of his he chopped the inside of her elbow with his other hand, receiving a jab to the ribs in return, as he maneuvered her arm so he had her in a shoulder lock. Turning her so she was between him and Tom he pushed her into him making sure to not jar her shoulder to bad causing them to get entangled in a mess of limbs.

Moving to finish the fight he slid right in between the two of them grabbing Kate by the neck as he put his knee across Tom's throat, lightly enough so it made it hard to breath but didn't cut off all air. Snaking his arm around Kate's throat he locked it with his other one applying a choke hold, once again not cutting off air but making it clear he could. Breathing hard at the exertion fighting the two of them caused him his own pants were mirrored by the two detectives. Realizing they were beaten fair and square Tom tapped him three times fast on the parts of him they could release indicating surrender.

Kate, however, used Tom's tapping out as the distraction she needed to throw her head back into Castle's causing him to loosen his grip enough for her to get out. Both of them rising to their feet squared off once again. Kate knew she was at a disadvantage, Tom was out of the fight and it was just her and Castle. Ever since Castle had started trying he had been throwing her around like a rag doll, mainly because she had no idea what the heck he was doing. Wait a minute she just may have stumbled upon a realization. Castle claimed that she was fighting Derek Storm, and if that was the case she should treat it like she was actually fighting Derek Storm.

This entire time she had been thinking about how Castle was so good when she should have been thinking about all of his books. Knowing each and every one of his books instantly Kate realized all she had to do was think about the fight scenes he wrote and how Derek Storm fought. Armed with this knowledge she realized she actually had some type of insight into what Rick was going to do next. Getting a little smirk on her face that was quickly matched by Castle she approached him with new found confidence.

Moving almost as if they were of the same mind the two of them met in the middle, but this time the results were vastly different from earlier. Instead of Castle quickly grabbing her and putting her on her back again she broke up his counter. Instead of actually hitting one another their hands turned into a blur of grabs, counters, and hold breaks with neither finding a firm purchase on the other. Ryan, Esposito, and Tom were a bit stunned by this new strange dance they saw in front of them. Rick and Kate moved around trying to find purchases one another only to have their holds broken. Soon they moved to elbows and knees realizing they were not going to be able to throw one another. Eventually after minutes of back and forth it came down to real experience versus the experience found from reading a book, and real experience won.

Purposely leaving his face open Kate took a jab right at Rick's head. Instead of batting it away or stopping the blow Rick instead leaned back out of range while grabbing her wrist with each hand then jumping off his feet. Propelling himself up he locked his legs around Kate's shoulder and twisted using his weight to bring her to the ground onto her back. Still latched on like a pit bull, Castle slightly altered his legs until he had Kate in an arm bar. Pulling her arm towards his chest and slightly lifting his hips he let Kate know that he had her arm in a position where he could break her elbow. None of the detectives had ever seen that move before, at least not in person, and Kate was subsequently forced to tap out.

Untangling himself from her, Castle regained his feet reaching hands down to help her up. Hauling up Kate he turned to walk back where he had left his cloths in a pile. Needless to say everyone was completely flabbergasted at Castle's display of physical prowess. Not only had he defeated two trained detectives, but he had done it with relative ease until the last bit with Kate. Only Esposito who had won all of his losses back and them some seemed happy with the entire outcome of the fight, well him and Castle.

Kate breathing heavy was the first to voice the question, "Where did you learn to fight like that Castle, and how come none of us knew?"

Castle stopping right before stooping to pick up his shirt looked at her before answering equally out of breath. "Well you know how I enjoy doing research for my books right, such as shadowing you?" he asked upon which Kate nodded in recognition.

"Well when I was creating Derek Storm I had trouble writing the fight scenes and decided I needed actual experience for them to be authentic. So with that in mind I contacted an ex-Delta Force hand to hand instructor and proceeded to spend sixteen months training with him. That is why the fight scenes tend to get better and better as the books go on. Anyway he taught me the military form of hand to hand combat known as CQC. Normally CQC is done with a gun and a knife which you see in the Derek Storm novels, but he also taught me the unarmed variety. CQC stresses quick takedowns, counters, joint locks, fighting multiple opponents, and generally using your opponent against themselves. This knife was a given to me by my instructor after I beat him," Castle explained while unsheathing an inch of the knife on his forearm.

"Dude I appreciate you getting my money back and then some, but why didn't you say anything earlier or for that matter start out better?" Esposito asked.

Putting on one of his trademark lopsided grins Castle couldn't help responding, "Where would be the fun in that. Now I believe we have a case to solve." With that he put his shirt back on, slipped on his shoes, and picked up his coat heading out the door of the gym leaving four very confused detectives behind.

Kate was the most flabbergasted of them all. For over a year he had been following her while she protected him and never once did she realize he was more capable than her. Making her mind up right then and there Kate decided that she would have to come up here with Castle much more frequently until she got as good as he was. Fighting with Tom had felt like a cross between flirting and foreplay, but with Castle… well with Castle it felt almost like full blown sex.

Smiling to herself at this whole knew side of Castle, Kate slowly walked towards the women's locker room to freshen up before going and finding out what Castle originally came to talk about. Besides Kate really needed some time to cool down, that last bit with Castle where each was trying to get a grip on the other had left her hot in more ways than one. Twirling her hair as she walked through the doors of the gym Tom was already a fading memory as her mind was particularly occupied with a certain author in a tank top. Kate just couldn't wait for a rematch.

The End

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