Disclaimer: I don't own Castle. However, the OC is mine.

Prompt #5: Fixture - He'd become the 12th's unofficial mascot or something.

Words: 1,137

Detective Miranda "Ash" Reynolds stood in front of the NYPD 12th precinct, taking a deep breath of New York City air to calm her nerves. A detective from the 42nd precinct's Arson division, she was now going to work at the 12th under Victoria "Iron" Gates in Homicide. It was going to be an amazing experience.

Miranda headed inside and made her way upstairs to Homicide. She stood in the entryway and let herself examine this new environment. Apparently they'd just caught a fresh case, as evident by the whiteboard covered in pictures, scribbles, and a timeline.

"Detective Reynolds?" Miranda saw Iron Gates herself waving from her office. Remembering everything she knew about the former IA detective, Miranda headed over. She could feel eyeballs from every cop in the room on her.

And she saw one man, a civilian, standing out in their midst like a virgin in a maternity ward, watching her just as closely.

Gates shut the doors after her. "Well, Detective, it's good to have you here. I understand you've made quite a name for yourself in the 42nd's Arson squad. "Ash" was it?"

Miranda nodded. "Yes Captain, that's what they called me."

"Well then, Reynolds, just to let you know, I run a tight ship here," Gates said, sitting behind her desk. "You're here on request because, frankly, this case is baffling. Report to Detective Beckett in the bullpen. She'll give you the information you'll need. You report to her."

Miranda nodded once again. "Yes ma'am."

"Don't call me ma'am. It's sir, or Captain."

"Yes sir."

Beckett wasn't there, but there was the civilian from earlier sitting next to her desk. Unsure of where to go, Miranda walked up to an officer and said, "Who's the guy at Beckett's desk?"

He didn't even have to look. "That's Rick Castle."

"The novelist?" Miranda clarified.

"One and the same. He's been around here for, oh, almost four years now? Shadows Beckett around on scenes. Says she's his inspiration for Nikki Heat."

Miranda had read the Heat series, so she nodded. "Wow. And he's actually useful?"

"Yeah. Say, you the arson detective from the 42nd?" When she nodded the officer chuckled. "Have fun with them. You always get weird cases with Beckett's team."

Now armed with some information, Miranda headed over to meet this Castle fellow. He seemed to be a handsome piece of man, but she reserved judgment until after. "Mr. Castle?"

He looked up and saw her. "Oh, hi. You looking for Detective Beckett?"

She held out her hand. "In time. I'm Detective - "

"Miranda Reynolds, from the 42nd, right?" he finished, shaking her hand. "Right. You're the arson investigator who proved that Manhatten couple was actually murdered by the fire and it wasn't an accident."

Her surprise showed. "You've read up on me?"

"A little." He gestured to the murder board. "Looks like this case may be right up your alley." She only managed to glance over the information before he interrupted. "So what's with the nickname?"

"Huh?" Miranda asked, not really paying attention.

"Your nickname. Ash, was it?"

"Oh, that. The older guys call me that because on my first case, I got covered in ashes when the rafters above me disintegrated. I looked like I'd been through a volcanic ash storm. It stuck." She pointed to one picture of the body. "Well, he definitely died there. See his arms curling up in front of him? Classic defense position. Only the living want to protect. The dead don't give a damn."

Castle nodded. "Yeah, Dr. Parish already confirmed COD was from inhaling superheated air."

Miranda's gray eyes darted over the crime scene pictures. "Can't tell for sure without seeing and smelling the place, but it looks like there was an accelerant used. A lot of the lame stuff, or a little of the good stuff." She saw him pull out his notepad and blinked. "Um, what're you doing?"

"Writing that down. Maybe if you're lucky, you can have a cameo in my next book." He looked happier than a kid with candy. "Hmmm, title could be Blazing Heat. Oooo! Heat Flash."

"Are you reaching that age now, Castle?" asked a new female voice sarcastically. A woman with long brunette hair came up and sat in the desk next to Castle's chair. "Hormonal imbalances messing with you? You know you can take a pill for that, right?"

Castle gave a very dry, very forced series of ha's before gesturing to Miranda. "Detective Beckett, Detective Reynolds. Miranda and I were theorizing about new book titles featuring arson."

"Castle, don't you dare," Beckett snapped, totally serious. "I don't care how much money they make, it's getting stupid how much you do that."

"Doing what? Utilizing my creative talents by using life to write fine literature?"

"Fine? Ha! Run down to the corner store and get some orange juice. Extra pulp for that fiction."

"Humph! Just for that, I'm putting an extra-slutty scene in there for you!"

In the background of their bickering, Miranda edged away and introduced herself to the two detectives who'd followed Beckett into the bullpen. They introduced themselves as Esposito and Ryan, part of Beckett's team. "You'll get used to this," Esposito told the arson specialist. "They fight like a married couple, but it's cool."

"And everyone's cool with this?" Miranda asked. Looking around, she saw that nobody was even bothering to look up from their paperwork to watch this (she thought) fascinating battle of words and wit.

Ryan rolled his eyes and scoffed. "Fine? This is practically golf commentary for us. Background noise."

"Wow." She gave the arguing writer and cop pair a grin. "Wonder what will happen if I decide to stick around a while after this case?"

"Always welcome to see. Just know this," Esposito advised. "No matter how bad it sounds or gets, Castle will always be there the next morning. He's like a bad penny the way we can't get rid of him."

Or, thought Miranda silently as she returned to looking at the crime scene photos, he's pretty damn sure about why he's here, and it's not just because of a book series.

But for now, they had a murder to solve. Clearing her throat, Miranda said, "Hey, just to interrupt, can I see the crime scene?"

So, I decided to pull a cute one and start doing what the show does. Anyone spot the Firefly tribute? Keep your eyes peeled for more!

Review please!