Disclaimer: I don't own the characters nor make any profit from this. This is simply a mental exercise for me. So, cut me some slack.

CH. 1 – The Surprise

A/N: I decided split the story up, chapters 1-4 of the old story will now be "Detective Richard Castle"; chapters 5-8 (so far) now will be "Detective Richard Castle: Isotope Chaos", as part of the DRC series. If you were reading, 5-8 which was formerly "New York, New Crimes" it is now: "Detective Richard Castle: Isotope Chaos". I apologize if this causes you any confusion, but I believe this way, each subsequent story can be treated as its own "episode" rather than part of one giant fic.


Detective Kate Beckett didn't mind Mondays, in fact, she looked forward to them. She looked forward to getting a new case or working on a current one – that is until he started to shadow her for his new book series.

But as much as Detective Beckett would like hate him for being the annoying man-child he is, she had to commend him on his investigative skills and his wealth of resources which without she probably couldn't solve half the number of cases she was given.

That said, this Monday would bring plenty of good, bad and strange news. Detective Beckett arrived as usual at 7:15, made herself a cup of espresso, from Castle's gift to the precinct and headed to her desk – only something caught her eye. She stopped at a new desk just to the right of hers, the nameplate read: 'Detective Richard Castle'.

"That arrogant jerk," She thought, "replacing his name on another detective's desk." She shook it off as another of Castle's pranks designed to get on her nerves and went her desk.

As the precinct began to come to life with the sound of chatter and computers booting up, in walked Rick Castle, his trademark grin plastered all over his face. He took his usual seat next to Kate's desk and greeted her.

"Good morning, detective, you're looking lovely as always." He said with a smile.

Beckett looked up from a file she was reading to reply. "What do you want, Castle?"

Castle just kept on smiling and said, "Oh, no, no, no, I don't want anything, I'm just happy to be here today, that's all." Continuing to beam with delight.

Beckett rolled her eyes and went back to the file. Glancing over at the desk she saw this morning she realized no one came and sat down at it or removed Castle's nameplate. She went back to file, but curiosity got the best of her and she just had to ask.

"So, I see you replaced another detective's nameplate, what are you trying to do: play detective?" She asked with a slight hint of annoyance in her voice.

However her question fell on deaf ears, as Castle wasn't even looking at her but at Captain Montgomery's office.

Beckett looks too then refocuses on Castle, yelling to get his attention, "Castle!"

It was enough to snap Castle back to reality, and he replied, simply, "Hmm?"

Now really annoyed, Beckett restates her question for full effect, "Why is your name on that desk?" She points.

Castle looks then looks back at Capt. Montgomery's office, "Oh that," he says nonchalantly, Captain Montgomery waves to him. "The captain can answer that, come on you are gonna love this."He says pulling her into the Capt.'s office.

"Doubtful."

He greets them both. "Detective Beckett, Castle, wait here."

Montgomery then calls in Esposito and Ryan, they join Castle and Beckett. Of the four, only Castle felt calm and at ease, it's not everyday the precinct's best detectives are called into the Capt.'s office, it's like a group of honor roll students being called in to see the principal – you don't know what's going to happen.

Montgomery takes his seat.

Looking around at her other detectives, Beckett decides to speak up. "What's this about, sir?"

Montgomery smiles. "All in good time, detective." He says with a slyness to his voice. "The Commissioner is coming down in few minutes to swear in a new detective and I want the four of you to see it."

The three detectives look baffled. A swearing-in ceremony, that's what this is all about and who is this new mystery detective anyway, seemed to be consensual thought, as they waited. Beckett looked over at Castle who was stone-faced; it was a damn good poker face. If only he used it for actual poker.

Esposito spoke to break the silence, "So is it anyone we know?"

Montgomery just shrugged ambiguously and said, "Yeah."

Ryan began to guess, "Is it Hopkins, Jones, Williams?" he guesses. He received no answer.

Beckett then turned to Castle, who was still wearing his poker face. "So, Castle you never did answer my question."

Castle looked at her and opened his mouth to say something but was cut off by the Captain greeting the Commissioner. "Hey Frank, good to see ya! How's Laura?"

The two shook hands and exchanged other pleasantries until finally Commissioner Downs said laughingly, "All right, enough sewing circle, I'm here to swear-in a new detective, right?"

He looked at Montgomery. Montgomery nodded.

Commissioner Downs cleared his throat and began, "Is Mr. Richard Castle present?" Castle stepped forward as Beckett, Esposito and Ryan stood in shock – Beckett more so.

Commissioner Downs continued, "Are you ready to take the oath?" Castle nodded and said simply, "Yes."

Beckett looked on dumbfounded, for two reasons, one, Castle was professional and serious and two, he was officially going to be one of them rather then a "consultant". Beckett snapped back just in time to hear, "Congratulations, Detective Richard Castle." The two shook hands.

And after chatting with Captain Montgomery about a Saturday barbecue, the Commissioner left.

"So, any thoughts?" the Captain asked.

Nobody said anything.

But soon Beckett spoke up again, "So, Castle's really a detective now, sir?" She asked, still not convinced that what had transpired was real.

"You were here for the ceremony weren't you, detective?" Responding with sarcasm. Beckett just nodded.

After a while the captain excused all of them except Castle. In private Castle was issued his standard, a SIG P226 (DAO) and badge (NYPD No. 34432).

Outside, Beckett, Esposito and Ryan were huddling around Beckett's desk discussing what just went down.

"Wow, he's a playboy, a celebrity writer and a cop," Ryan says, looking back into Montgomery's office, "Dude's a serious overachiever."

Beckett looked up and scoffs, "Oh, please if anything Castle's doing as a publicity stunt for his book."

"So what, you don't think it's official," Esposito asked, "Sure looked legit to me."

"Maybe but so was Shaq's swear-in as volunteer cop a few years ago." Ryan chimed in as Castle stepped out of Montgomery's office. smiling with his hands out-stretched.

"Huh, huh, was that worth it or what?"

"We'll see, but for now, welcome to the force, bro." Esposito said as he and Ryan exchanged high five's and fist bumps with Castle and left Beckett alone.

Castle sat down next to Kate, "So, Kate what'd ya think?"

Kate pulled her face close to Castle's, looked him in the eyes, and said, "Now I don't have to worry about you as much, kitten."

The smile that was on Rick's face disappeared, he hated that nickname and what's worse he hated when Beckett used it against him.

He got up but before left for his desk he whispered in her ear, "Very funny."