A/N: Hello everyone. I have been thinking about writing a fic like this for months. Now I have never written Dark!Killian before so this fic will be an exciting writing challenge for me. Also as a warning, the prologue and the first chapter will be rated T, but from the second chapter onwards this fic will be rated M. I hope you guys enjoy the first chapter. Thanks for reading!

-/-

Killian Jones shifted from from foot to foot as he peeked around the tree he was hiding behind, scanning the edges of the clearing for any other signs of movement.

Hist fingers curled around the hilt of the dagger sheathed at his hip. After nearly three centuries, he'd finally found the weapon powerful enough to kill the Dark One. At last, he'd have revenge on the bastard that had stolen his life away from him, his love, his Milah, and his hand.

All he had to do was plunge it into Rumplestiltskin's heart, and the world would be rid of the demon.

He took a deep breath before emerging from his hiding spot. He moved to stand in the center of the shadowy clearing. "Dark One, I summon thee," he said, holding the dagger aloft.

Then he appeared in a puff of red smoke. "Ah, pirate, it took you long enough. You found out about the dagger a year ago and it took you this long to find it? Isn't that what you would call bad form? A man doesn't like to be kept waiting."

"You're not a man," snarled Killian. "You're a bloody demon."

Rumplestiltskin merely laughed, the gold in his teeth flashing with menace. "Well, dearie, get on with it," he said, spreading his arms wide. "Put an end to the centuries old feud."

Killian willed himself to move forward, but he remained in place as if frozen.

Rumplestiltskin grinned. "Or do you not have it in you? Does your silly code of honor prevent you from killing an unarmed man? Or are you just too weak, too worthless, to take your revenge. Perhaps it's good that I killed Milah when I did. It would have broken her heart to know that her 'twoo wuv' was a coward when it really counted."

The words were just enough to provoke an attack. He removed the dagger from the sheath and lunged forward, taking pleasure as the dagger pierced Rumplestiltskin's heart. "Don't you dare talk about Milah. You are unworthy of even speaking her name."

"It hardly matters now," said Rumplestiltskin calmly, looking down at the dagger in his chest as if it was nothing more than a shallow flesh wound.

Then the little remaining light in the clearing was snuffed out. Rumplestiltskin's bone-chilling laughter began to ring throughout the clearing. "All magic comes with a price, dearie, and now it is yours to pay."

"What in the blazes are you talking about," demanded Killian, his hand still on the hilt of the dagger.

"We made a deal a year ago, dearie. You agreed to fetch the dagger and kill the Dark One. Well, it looks like you made a deal you didn't quite understand."

"Impossible. The man I spoke with was a simple peasant," but then Killian's face crumpled. "It was you, wasn't it. It was you all along. You set me up."

"Indeed I did," said Rumplestiltskin. "Ever since the Evil Queen's curse failed there was nothing else in left in this world for me. I needed someone who was hellbent on my demise to take my place, and fortunately for me, you had just returned from Neverland."

"But why," spat Killian. "Why would you give up all your power?"

"Because it couldn't get me what I 's the worst curse imaginable to have all the power in the realms, and yet, still have what you desire most elude you. It's a fitting punishment for you, Jones. You've spent centuries with nothing in your heart but darkness and revenge, fighting to avenge your lost love, and now you'll suffer an eternity knowing that no one will ever love you. It is impossible to love the Dark One."

All the color drained from Killian's face as Rumplestiltskin's body went limp with lifelessness, and his eyes slid closed, his lips twisted upwards in a victorious smile.

Killian gripped the dagger, removing it from its prison. The curvy blade was dripping with blood, and now a new name was etched in the steel.

Killian.

He suddenly felt all the power in the realms flow into his body. It tingled beneath his skin, and he was raised to his feet. His entire body felt like it was being engulfed by a raging inferno. The letters of his name lit up like stars. Then he heard the thud of something hitting the forest floor. He looked downward only to find his hook on the ground, glinting in the darkness. In its place was his hand, at long last returned to him.

Gone was the pirate captain that he had become, and in his place, a new and terrifying man. The new Dark One.

"No," said Killian, his hand shaking, has he fell to his knees. "Milah, I failed you."

He'd spent centuries pursuing revenge and now he was doomed to become exactly like the man he despised most in the world.

Tears glistened in the corners of his eyes. The dagger was warm in his grip, and he knew he would have to go where no one dared to venture. The Dark One's castle.

Killian, had no idea how magic functioned, but he new that with his new powers it was likely that whatever he desired to happen would happen without a single though. So he pictured the towering spires of his enemy's castle.

Seconds later he found himself in the cavernous great hall of the Dark castle. His new home.

No. It wasn't a home. It was a prison. But at least here, he'd be able to live out his eternity undisturbed. He'd be forever cursed, but it hardly mattered.

Killian climbed the stairs and locked himself away in the chamber of the highest tower. The mere fact that Rumplestiltskin had lived here for centuries made his stomach churn. He'd be forever reminded of the man who had taken everything from him. Just the thought was enough to drive him insane.

No. Killian would have build his own castle. A better prison. And just like that, the walls of the castle began to crumble around him, dissolving into nothing. Such was the power of the Dark One. He could decimate entire villages with such power.

Killian stood in the middle of the the empty valley and idly began to imagine the castle of his boyhood dreams. With walks of dark stone, and towers topped with gold, and windows facing out towards the sea. He gripped the dagger in his new hand, and was instantly transported to the furthest reached of the Dark Kingdom, by the sea. The castle materialized out of thin air, dark and looming over everything around it. It would be a fitting prison, he thought, and he'd be nearly impossible to reach, unless he so desired.

Killian straightened his shoulders. He'd always been a survivor, and now that it was his fate to live forever, he'd soldier on. The heavy wrought iron gates of his castle flew open, and Killian walked through the dreary courtyard. He passed the the doors of the castle and proceeded to one of the rooms overlooking the sea.

At least one thing of his old life remained. His eternal love of the sea. It was the only good thing left in his life that he had to cling to.

Everything else was cloaked in darkness.

-/-

In the neighboring kingdom, a royal christening was in progress.

King David and Queen Snow white held up their newly born daughter, swaddled in the softest silks. "Her name is Princess Emma," announced Queen Snow, "and she is the product of true love. Now that we have defeated the Evil Queen, I promise you that our family will usher in an era of peace and joy for this kingdom."

The denizens of the kingdom erupted into thunderous applause. "Long live King David! Long live Queen Snow! Long live Princess Emma!"

As the kingdom rejoiced, the magnanimous King David and Queen Snow White basked in the bliss of their victory. Not even suspecting that one day their joyous days would come to an end, and the light of their lives would be taken away from them.