Full Summary: Arthur Pendragon: blood spatter analyst for the London Metropolitan Police by day, vigilante serial killer by night. Following Uther's Code, a guideline for how to not get caught, given to him by his late father, Arthur only kills those who truly deserve it. However, when a new killer who could know the mysteries of Arthur's past arrives in town, it gets harder for Arthur to conceal his secret from his life-long friend, Merlin Emrys, who could get into the SCD's Homicide division if only he could find a solid lead on this case.
Pairings: Merlin/Arthur, Gwen/Lancelot.
Rating: M [gore, violence, sex, drugs]
Disclaimer: I do not own BBC's Merlin or Showtime's Dexter.
Note: This is an extremely bastardized version of Dexter seasons one and seven, so even if you've never seen an episode, you'll be fine. Also, forgive me if there's any inaccurate information about the British police here. As an American, there's only so much I can research without firsthand observations, but I can sure try.

Chapter One.

The full moon was the only body visible in the endlessly black sky. It's pale light illumined the cobblestone walkways and patches of greenery outside the tall, brick buildings of the campus. The glass double doors of one academic building swung open gently, revealing a dark-featured man in a smart, tight suit. His black shoulder-length hair was pulled into a loose ponytail so that layered strands fell about his eyes, and he scratched idly at the scruff on his chin as he walked down the path towards the car park, where only one car now remained.

Professor Cenred Russo withdrew his keys from his pocket and clicked a button. The car beeped and its headlights flashed as the doors clicked open. He got inside and settled in, placing his briefcase on atop the passenger's seat and pushing his key into the ignition. Just as the engine roared to life, there was a quick, faint whooshing sound from the backseat, and Cenred gasped as he felt a metal wire dig into his throat. There was a tug from behind, and his head was forced against the headrest.

"Do exactly as I say and you may live a little longer," came a low voice from the seat in back of him.

Cenred struggled to breathe, and the fishing wire around his neck slackened slightly. He chanced a look around but, before he got very far, the wire was tugged harder, and Cenred gagged as his head was thrust backward again.

"No peeking," the voice said and, if it weren't for the piercing blue eyes in the shadowy rearview mirror and the wire across his tender skin, Cenred would have thought the darkness itself was speaking to him.

"What is this? Who are you?" Cenred asked, his voice shaking, when the wire slackened again. He didn't risk turning around this time.

The man didn't answer his questions, but instead said in a droning tone, "Start driving. I'll tell you were to go. And don't—," the wire tensed warningly for only a moment, "—try anything stupid."

Cenred did as he was told, and they sat in silence for the thirty-minute car ride, save for when the man in the backseat muttered commands on when to turn and what to do next. As they left the city behind and started driving through the winding outer limits, Cenred dared not speak, but his mind was constantly racing, trying to find a way out of this. His heart was threatening to beat straight through his chest, and his breathing was coming up shallow; and he was torn between wanting to drive as slowly as possible, that way whatever was coming would be prolonged, and speeding up, due to a morbid curiosity leaking into his brain. Every so often, he cast wary looks into the rearview, trying to determine more features of his captor, but all he ever saw were those bright blue eyes.

Finally, they had arrived at their apparent destination: an abandoned hunting cabin nearby the banks of the Thames. It was secluded, not another structure for miles, but Cenred could still see the twinkling lights of London in the distance. His wife was somewhere in there, wondering why her husband had not gotten home yet.

The wire whipped itself away, releasing his bruised neck, and Cenred let out a gasping sob. He didn't know why the simple fact that he was never actually going to make it home decided to hit him in that moment, but it did.

"Please," he breathed. "My wife—"

"—Doesn't know about your affairs, does she, Professor?" the man cut him off harshly.

Cenred stammered. "How—?"

However, something cold and thin pierced his neck, and he'd only registered it as a needle right before the darkness became all-consuming . . .

Consciousness rushed back to him with a jolt, and his nostrils burned with a lingering foul scent. He knew at once that he'd been awoken by some kind of smelling salt. He attempted to sit up, but he found he couldn't move his body. His entire form was completely restrained by, he saw once he calmed himself enough to look down his nose, plastic wrap and glistening silver duct tape. He was on a rickety table inside the hunting cabin, and more plastic sheets lined the walls, blocking the windows and door. The only sound he heard was his haggard breathing, right before a bright white floodlight was switched on to his right. He winced until his eyes adjusted to the brightness.

He felt a presence above him, and looked up to find a handsome, golden-haired man looming over him. He looked strange against the black backdrop, as though someone like him should only belong to the sun; however, Cenred saw those same icy blue eyes as before boring into him.

"What do you want?" Cenred choked out at the man's blank expression. "I don't have very much money!"

A corner of the man's lips twitched upwards in an amused, micro-smirk. "I'm not interested in what funds you may or may not have," he said matter-of-factly. "I assume your wife will need those savings for the memorial, anyway. I'm afraid she won't have a body to bury."

Cenred was at a loss for words.

In the pause, the man reached towards a small metal table to his left and picked up a scalpel, which he used to trace a thin line into Cenred's cheek. The cut stung and trickles of blood came from it, and the man collected a drop. He dabbed the blood into a sample slide inches above Cenred's eyes, and Cenred looked on in horror as the man placed the top onto the slide, causing the droplet to expand into a flat, crimson circle.

"How many students do you think take your course each semester, Professor?" the man asked as he once again slipped from view, and Cenred hung onto his every word. "I don't guess you've ever counted, because all that every mattered was the one. One girl each semester that you handpick and fail on every assignment until she begs you for extra help, which you graciously give in your office after hours.

"She's probably happy for it, too—to spend time with a cool, handsome teacher like yourself. And, in time, in becomes more than just a study session." There was a mirthless laugh emitting from the darkness. "Oh, and the brain on you! Chemistry is a difficulty topic, after all. She's bright-eyed and fascinated by you—can't believe you'd fall for her."

He appeared above Cenred's right side, his silhouette blocking out the bright light.

"And imagine her surprise when your hands are wrapped around her neck, suffocating her," the figure said with a smirk, cocking his head to the side as he took in Cenred's sweat-matted hair sticking to his temples. "They're all easy targets, really, the lot of them."

The man looked up to the wall opposite him, and Cenred followed his gaze. On the plastic hung seven printed photos in a row, all of them depicting the bright smiling faces of young blonde co-eds.

Cenred felt his breath leave him. "How could you possible know—?"

"That doesn't matter," the man snipped, looking down at him with a cool indifference. "All that matters is the lack of evidence you leave behind. The police have never been able to pin you for the murders. They have to follow a protocol, a code, but—"

The shadow withdrew again, reappearing seconds later on Cenred's left with a clean, mirrored knife held in his gloved fist. The knife caught the light as the man raised it and steadied it directly above Cenred's heart.

"Luckily, I follow a different code."

"No!" Cenred begged—yelled, although he distantly knew there was no one who would be able to hear. "No! No!" He tried fighting against his restraints, but they were too tight to allow movement.

The last thing he registered was the glinting blade crashing down, a sharp pain in his chest, and a heavy feeling as crimson oozed out around the knife and dripped down the plastic-wrapped curve of his chest.

Arthur Pendragon picked up the last heavy-duty black trash bag and tossed it over the side of his boat, hearing the splash it caused before sinking to bottom of the river but not really paying it much mind. It was too cold to care about anything else but getting to the warmth of his bed, and he rubbed his gloved palms together fiercely. The friction caused a heat that diminished the second he stopped the movement.

With a single glance at the cold, black waters surrounding him, he returned to the steering wheel and turned the boat around, headed back for the city. He could see the banks of the river on either side of him, but the land was nothing but fields and distant rolling hills in this area. No one would ever be around to see him dump the bodies, leaving the weighted bags to be carried off downstream by the current, into the English Channel and, eventually, get lost in the Atlantic.

This was a tradition Arthur had perfected over the years. He'd figured it out by himself, as it was not specifically listed in Uther's Code, which had been taught to him by his dearly departed father, a renowned Detective Inspector for the Metropolitan Police. Arthur did not kill his father: that had been cancer's doing, in the same way Arthur's mother had gone before he had any real memory of her. However, before Uther passed on, he used his knowledge of police protocol and forensic investigation to create for Arthur a strict set of rules so that he would never get caught. Through them, Arthur had been trained to kill practically since birth.

Arthur had taken these rules and lessons to heart. After all, Uther could have sent Arthur to an asylum when he was young or alerted his colleagues. Instead, he let Arthur be free to be himself—to give in to his urges, but in a way that was beneficial to society. Above all, Uther taught Arthur to kill those who truly deserved to die: the murderers that had been let off, the killers that got away. They needed to pay for their misdeeds, and Arthur saw to it.

The sun was forming a pink line on the horizon as Arthur neared the city, and light drifts of snow fluttered down from the sky. Arthur pulled a lever back to speed up the boat, leaving a slice of foamy waves in his wake.