A.N.: okay this is my first NCIS, Castle and crossover fanfiction, so i hope I do all three justice. this one has been in my head all day now, i feel like it's... it's worth writing down. so i hope you enjoy it, despite it being a WIP and relatively short. now i'm not a fan of author notes, so this will probably be the only one until the very end, please leave a review, i really enjoy criticism and hey burn me if you like.

Disclaimer: my usual disclaimer is found on my profile, but this is the first tv one i've done, so; All names, places, organisations and similar are fictitious and all familiar content is owned solely by Paramount, Bellisarius, ABC Studios and Beacon Pictures. no money is being made from this story.

A single shot rings out in the darkened house. A small figure slumps over on the writing desk, a hand sliding off the laptop's keyboard. Blood begins to soak a book manuscript. A single shell casing drops to the floor, rolling under a couch out of sight. A masked killer puts away his gun and leaves; his job is done.

[0]

Detective Kate Beckett sits at her desk, head in hands as she mentally prepares herself for a day's worth of paperwork, Detective's Esposito and Ryan are nowhere to be seen, neither is her partner Castle. She stifles a snort, Richard Castle, mystery author extraordinaire, hating on paperwork. A contradiction of terms for anyone who did not know the man. The elevator opens behind her and three figures step out, one holding two coffees, the other two bantering over who was better at archery.

Castle leans around her puts down her coffee in front of her bowed head, surprising her for a moment,

'So, I hear that today's agenda is paperwork. Where do we start?' he says smiling.

She cocks an eyebrow, not believing that he's serious.

'You're going to help me do paperwork?' she asks incredulous.

'I distinctly remember the last time I opted out of helping you with paperwork ended up with me being held hostage in a bank with my mother. So yes, paperwork.'

She hides a smirk, 'There's no murder in our jurisdiction to solve today, just a whole lot of files to write up.'

'There's no murder in your jurisdiction to solve yet,' he corrects her whilst reaching across for a pen, 'it's still early.'

[0]

Tony DiNozzo was napping at his desk as he waited for his team and boss to arrive at work. With feet propped up on the desk and his head tilting sideways onto his shoulder, a mouthful of saliva was not far off from becoming drool on his chin. In front of his desk stands both Ziva and Timothy, suppressing their laughter.

'Tony!' calls out Ziva, shocking him from sleep. He almost falls from his seat as he jolts back into full consciousness,

'I wasn't asleep!' he claimed,

'Oh really, so the snoring was just to throw us off guard?' jibed Timothy,

'Very funny McGeek, but I don't snore.' Tony shot back. Ziva smirked at them both before turning to her desk.

'Do we have a case to go to?' she asks them both after she has stowed her bag.

'Not as of yet, haven't seen Gibbs today.'

As if by coincidence, or good timing on his part, Gibbs chose that moment to open the doors of M-Tac and make his way down the stairs,

'Pick up your bags,' he said striding past them, 'we got a case.'

[0]

With sunlight peeking through the closed curtains, the house still had a creepy feel to it. That feeling was not reduced by the body with a single gunshot wound to the head, and a pile of dried blood gluing eight hundred or so pages of a novel together.

Kate Beckett strode into the room, closely followed by Castle and Detective Esposito. Lanie Parish was already there, her kit ready to go.

The officer currently in charge of the scene briefed Beckett on the victim,

'Name's Leanne Doyle, twenty-two, university student and budding novelist writing her second mystery novel, home schooled, dad's listed as a Navy captain, mother's deceased. As far as we can tell she suffered a single gunshot wound to the back of the head, we recovered a casing under one of the couches, looks like a .38.' Kate nodded as she took in the scene; the young woman had been working on her computer when she was killed, her long brown hair fanned out along the desk, falling over her shoulders and across her face.

Scanning the room, she looked for anything out of place, 'What are we looking at here?' she wondered aloud.

The officer who had briefed her jumped in, 'Nothing was taken, wallet and cash are in her handbag by the door, phone, mp3 and other valuables were untouched. It looks as though the shooter came in, delivered the shot and left, we found no prints, no blood trail, no evidence of a struggle, hell it doesn't look like she got a chance to turn around.'

Beckett thanked the cop and turned back towards her team. The first thing she noticed was Castle expression, it was one of horror.

'What's wrong?' she asked him,

'Leanne Doyle, the young mystery writer,' he said quietly, 'I knew her.'

'How?' she asked,

'She used to come to my writer's workshops I held on a weekend a few years back, I still remember the first time I met her. It was a Stanton library, she couldn't have been older than sixteen, yet she had not only read all of my books, but all of the top rated mystery novels you could think of, and a whole piles of ones you wouldn't have. I remember her because she came in with a copy of Flowers For Your Grave, which she had not only done an edit that would make my editor cry with humiliation, but she had also annotated it with things she would have done differently. It was a fascinating read, I borrowed it for a fortnight, she let me get copies of all her notes. She was a brilliant kid, I got her signed up to my publisher and her first novel, Gunshot was an instant hit a couple years back.'

Beckett nodded, vaguely remembering the book he was referring to, and put an hand on his arm in comfort. Lanie had moved the dead woman to the floor and was going through the preliminaries. She looked up from her position on the floor, her eyes flickering back to Castle's stricken face before addressing Kate,

'T.o.d. estimated about two am this morning, which would coincide with the sound the neighbours heard but passed off as a backfiring car. Single gunshot wound to the head, size would put it at a .38 calibre, shot from a distance, there's no sign of gunshot residue on the body, no burns that would coincide with it being a close-up shot and there's no other visible external injuries.

'Right, we need to get in contact with anyone who has seen her recently, neighbours, friends, employers, the friend that discovered her, what about her dad, you said he was a marine?'

[0]

Gibb's team pulled up the curb outside the house to discover an investigation well underway. Ziva, Tony and Tim went straight to work, cameras and evidence markers at the ready. After looking around for a moment Gibbs spotted woman who was clearly in charge, her uniform stating she was an NYPD detective.

Walking over to the woman he noticed that his team had given up on attempting to gather evidence, as the NYPD has already done the work and had already started bagging anything considered to be evidence.

The NYPD detective noticed Gibbs and made her way over to them,

'Detective Kate Beckett, NYPD Homicide , can I help you?' she announced as she reached them.

'Special Agent Leroy Jethro Gibbs, NCIS.' she shook his hand,

'Sir, with all due respect I think you'll find that this murder is wasn't of a marine, the victim's father was, but records show he's on current deployment.'

'That's the issue Detective Beckett, Captain Doyle returned from active duty last week, last seen leaving the airport and getting into a cab. You're dealing with a civilian homicide, I've got a missing marine.'

Beckett nodded, knowing it would be useless to argue, 'Sir for our departments to work this case together, you would have to contact my Captain.'

'And who might that be Detective?' he asked as he reached for his phone.

'Captain Victoria Gates, Sir.'

[0]

A phone rang inside Captain Gate's office, caller ID showing it wasn't one of her regular callers. She picked up the phone with slight trepidation, 'Special Agent Gibbs, long time no hear.'

'How you doing Iron?' came the reply.

[0]

Kate Beckett did her best to hide her shock as the NCIS agent referred to her captain by a nickname only used behind her back. She waited as Gibbs explained the situation to her and asked how easy it would be to coincide investigations on the case. From what she could hear her captain was delighted to have NCIS on board, and would glad to host his team at the precinct.

Gibbs readily agreed, stating that it would have more room than NCIS headquarters, but they would be able to access each other's files for the duration of the case, and should it become necessary, they could all use the technology provided at NCIS HQ.

After that phone call was done, Gibbs excused himself to make another to Leon Vance, his boss to get the final stamp of approval. Tony stepped up and introduced himself and the rest of his team, stating it would be a pleasure to work the case with the NYPD.

Castle had snapped out of his stupor and rejoined Beckett over by the agents. Beckett introduced him as a civilian investigator aiding her team, much to the amusement of Tony.

'You're Richard Castle, the author, right?' asked Timothy,

'That's right,' he paused, 'Special Agent McGee.'

'I'm a mystery author myself actually, got a couple published so far and another in the works.' Timothy replied.

'Really?' Castle's interest grew, 'which ones? I don't think I've ever read any by a McGee…'

'Pseudonym.' was Timothy's explanation, 'I write the Deep Six series.'

Castle's eyes grew wide as he turned to his partner, 'Deep Six!' he turned back to McGee, 'I knew that kind of awesome couldn't be made up! I tried to get a real name out of my publisher so I could discuss plot development and experience, but they were tight lipped on that front, and I couldn't find a Thom. E. Gemcity anywhere!'

Beckett rolled her eyes at Castle's praise, and took to watching the other NCIS agents as they waited for their boss to finalise the agreement with their superior. Agent DiNozzo seemed amused at the author's conversation, quietly whispering a jibe to the agent beside him, a comment that was met with an elbow to the ribs and a 'Shut up Tony.'

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