Do you ever come up with a good idea, but at the same time, you feel like you're not capable of doing it justice? For a while, I considered passing this concept on to a better, more experienced writer before finally sucking it up and trying to execute it myself. This is my first true AU, and it's been a bit of a struggle, but I think I'm happy with what I have so far. A big thank you to my friend Suzanne (suz24) for beta-ing.

My goal is to update at least once a week, and I have enough material to last a while at that rate. I'm a little worried about how this plot might be received, but let me know what you guys think.

Summary: There are two kinds of folks who sit around thinking about how to kill people: psychopaths and mystery writers. He threw away his chance to be the kind that pays better. Very AU.

Rated: T for language and violence

Disclaimer: Definitely not.

So much of life is spent waiting. Waiting for the coffee to brew, the bus to come, the storm to pass.

Most of his time is spent waiting on others, observing them, like fleas under a microscope. On this particular night, it's taking longer than usual. He looks at his watch, and it's 1:30 am on a Friday night, just about closing time for Reilly's Pub. So what in the world is the hold up?

Patience. Patience is key. You get antsy, you get exposed. Besides, it's not as if he has anywhere else to be. All this waiting and plotting…sometimes it's half the fun.

There's movement at the entrance. That's him; it has to be. His target walks out of the tavern, clearly inebriated and dragging his feet. Middle-aged, wide frame, fairly tall.

He creeps closer, shrouded by the darkness of the alleyway to make sure. He always makes sure. This isn't a crime of passion. It's deliberate, premeditated, but never unjust. Those proven innocent live, and the guilty? Well, they sealed their fates long ago.

Here, in this alleyway, he is the law. Judge, jury, executioner.

The man stumbles, and in a flail of limbs, he crashes to the ground on his hands and knees, vomit spewing from his mouth. Disgusting, pathetic. To keep him here on Earth any longer would be a disservice to humanity.

He continues to retch onto the pavement long after all substance is gone, gagging on his spit. No. No one will miss him, of this he is sure.

It's time to make his presence known. "Marshall Greene."

The man in question coughs once more and then looks up with bloodshot eyes. "Do I...do I know you?"

"No, you don't know me," he answers honestly. "But I know you."

"Y-you do?"

"Yes, I know all about you." He helps the drunkard up onto his feet. "You're a people person, always have been. A real talker, but not much of an intellect. Lived in Queens, married for seven years. You could never hold down a job, and that didn't make the wife very happy, did it?"

Marshall's face blanches. "Man, I don't know what yer talking 'bout, but-"

"I think you do know what I'm talking about. You know very well, and so I just have one question for you," he pauses for effect. "Why did you kill Darla Greene?"

"Get offa me," Marshall groans as hands grip his coat. "Get the fuck off me!"

"Listen to me." he growls. "Why did you kill your wife?"

"I didn't!" He begins to panic in his grasp, almost falling over in his struggle to get away. "Not guilty, man! The court ruled not guilty."

"You think I care what the court has to say, you piece of filth?" He keeps his left hand on the man's collar and reaches down with his right for the rope. "Tonight, you answer to me. Why did you kill your wife?"

"She was a bitch!" blurted Marshall, the alcohol rendering his filter useless. "All she did was complain about the rent and the money and my job. She was, she was asking for it. I couldn't take it anymore!"

Confessions didn't happen so easily every time. He had to hand it to whiskey, as good as any truth serum. "That's all I needed to know."

The man looks down at the rope and then back at his face, realization dawning. "Holy shit. It's you."

"So you have heard of me. Then you know what happens next." He lunges, backing Marshall Greene into the brick wall, anchoring him there with his body, and then using both hands to wrap the line around his neck.

"Oh, God," Marshall chokes, tears welling up in his eyes. "No, please. Please don't do this, man. I'll do anything. I don't want to die."

It's futile to beg now. The rope tightens, slowly cutting off the airway, leaving the man to squeal and claw for his life.

"You should have thought about that before you murdered your wife." A life for a life. It's only fair. Killers get what they deserve. He likes to think he's the exception to that rule. It's either that or admit that he owes the world his life fifteen times over.

"Mercy," the man cries out with his final breath. "Mercy."

Something snaps, the squirming stops, and the dead weight of Marshall's body signals that it's done. He sets the man down and bends over to press the lids of his lifeless eyes closed.

Richard Castle doesn't show mercy.

Thanks for reading. Expect an update on or before next Thursday. I'd be grateful to hear your thoughts, so leave feedback down below, or shoot me a message on tumblr.

On an unrelated note, the Castle season 6 premiere is less than two weeks away! How excited are you?