The knocks echoed within the hollow wood of the door. The front step was dark, and Beckett couldn't resist the shudder that shook her body.

"Cold?" Castle queried, about to take off his jacket.

Beckett looked to her feet. "No. Just a bad feeling."

Castle nodded, the unspoken words between them hanging in the cold air. Castle turned in a circle, thrust his hands deep into his pockets and stared at the view of the city. Beckett knocked again, this time speaking, "NYPD."

Castle wandered down the steps and over towards the driveway, normal grey cement. No car was parked in the driveway and the flowers were fighting a losing battle against the weeds in the flowerbed.

"No answer?" He called to Beckett.

"No. I'm going round the back to check it out. You're coming with me," she grabbed his jacket sleave.

"Whoa, what brought on this change?" Castle laughed. "A few months ago you handcuffed me to the car to stop me following you."

"Don't think of it as a compliment, Castle. I don't trust you on your own. I'd rather you be where I can see you."

"Oh."

"Not what you were expecting, huh?"

"No, I was thinking more along the lines that you had finally begun to trust me and saw me as a valuable asset to the NYPD team."

"In your dreams, Castle." Beckett rolled her eyes as she pushed the back gate open.

"Wow. Great security," Castle commented, looking around at the lack of locks or security fences.

"You live in an apartment, how is that more secure?" Beckett queried, almost stopping.

"Well, for starters, I have security cameras. Trained on the door from inside. And there's some secret things around the place that you don't need to know about."

"Castle!"

Castle jumped. "What?"

"Are they legal?"

"Of course they are! What do you take me for?"

"You? Well you're unpredictable."

"Thanks."

"Castle, quiet."

"Sorry."

"Don't say sorry."

"Sor-."

Beckett pushed the gate open, her gun raised. She motioned to Castle to be quiet, spinning quickly to survey the house. The window leading into what appeared to be the lounge room was smashed, glass shards scattered across the wooden decking. Beckett slowly motioned for Castle to follow her, then handed him a spare gun.

She leant in close and whispered to him, "This isn't a toy. Don't aim and pull the trigger unless you want to blow something apart. Please, don't aim it towards your feet or anything stupid."

Castle nodded quickly, his mind far away from his body. He was James Bond, 007 Agent. He slinked towards the back door, quietly placing his feet around the glass.

Beckett pushed the door.

It opened.

She stepped in quickly, gun raised.

Castle followed.

Beckett led the way through the lounge, holding the door towards the bedroom open. It was dark and smelt stale.

Beckett motioned for Castle to follow her, and then she entered the room. Castle raised his gun, quickly turning to survey their backs before he stepped through the doorway. He saw a shadow shift quickly on the lounge room floor, and poked Beckett hard in the arm. She didn't turn instantly, as she was motioning towards the walk in wardrobe on the other side the room. Castle shook his head urgently, before running quietly out the room.

"CASTLE!" Beckett whispered loudly.

Castle quickly stepped towards the bookcase, then surveyed the room. He saw the shadow, which led to a leg. Castle's eyes followed the body, and then he saw the hand of the body over the edge of the couch.

The hand held a gun.

Aimed in his direction.

Castle fired on instinct, the bullet slicing the through the air and straight into the leg. The person moved sideways, the torso hitting the floor.

"NYPD! DROP ALL WEAPONS!" Beckett ran into the room, before noticing castle.

"YOU?"

"Me?" Castle squeaked, his hands raised in a protest of innocence.

"Are you okay? Who fired the sho-"

At this point, Beckett noticed the body on the floor.

"Oh my god Castle, you SHOT SOMEONE," she shouted.

"It was an accident! I saw the leg, the hand with the gun, which is aimed towards me, and I fired. I'm sorry!"

Beckett went to inspect the body, bending quickly to inspect the pulse.

"He's dead, Castle."

"I KILLED SOMEONE?" Castle wailed.

Beckett sighed. "No, he was already dead. Relax."

"But it moved. I saw the shadow. It moved," Castle's words shook.

Beckett stood again. "He hasn't been dead long. Body's still warm, so it was probably the body just moving. As they do."

"Wait. You're saying the dead move?"

"No Castle. I said that the body just adjusts, you know, like when you pass out. Your body falls to the floor. You don't stay on your feet."

"Oh. That!" Castle laughed with relief.

"Hey, relax." Beckett moved towards him, rubbing him softly on the arm. "You didn't kill anyone, and you acted on instinct. What made you look around?"

"I don't know, bad gut feeling, I guess."

"I did check."

"I know, I saw that. Just when you walked into the bedroom, I felt this urge to double check our backs."

Beckett smiled, her tired eyes warming.

"Good job, Castle. If he'd been alive, you could have very well just saved our . Let's head back to the precinct, and grab a warm coffee. We'll get Lanie down here right away, but first you need to get your head back on this planet." She gave Castle a quick hug, before guiding him gently towards the back door.