Disclaimer: I don't own either Harry Potter and NCIS. If I did, it wouldn't be nowhere near as good as it is.

Hello all! Was thinking of writing a Harry Potter/NCIS Crossover and this is what I thought of for a start. This is my first ever story which I would appreciate feedback on. Please don't be disrespectful though, still have a lot to learn! Thanks !

UPDATE: 07/05/2014 Made the fight scene a little bit longer, hopefully more interesting, as always, let me know what you think. Chapter 2 will be up soon.

Summary: Harry defeats Voldemort in the department of Mysteries and decides he's had enough with the wizarding world and leaves it behind to go to America with his godfather Sirius. But what happens when Harry crosses paths with our favourite NCIS team? No Horcruxes! Sirius lives! Kelly&Shannon live! Rated T to be safe. Harry/Kelly in later chapters.

The battle is in full swing. Members of the Order of the Phoenix and the death eaters were fighting left right and centre. Tonks was fighting Bellatrix, Moody fighting Rodolphous and Lupin was fighting Dolohov. In the middle, near the veil, Harry and Sirius were fighting Lucius Malfoy. A thin layer of sweat covered Harry's face as he battled to protect both himself and Sirius from Lucius's deadly spells.

"Stupefy!" Harry shouted, hoping to distract Lucius enough so Sirius could find an opening. The spell bounced harmlessly off of Lucius's shield and began to laugh.

"Do you really think a simple stunning spell would finish me Potter. Ha-Ha-Ha! It seems the dark lord was right not to think off you as a superior opponent!" Lucius sneered back, unaware of Sirius getting ready to strike.

"Maybe," Harry replied. "Or maybe I'm just distracting you from who you should be keeping an eye on. NOW SIRIUS!" Before Lucius could react to the sentence, he was struck with a powerful bone breaking spell. He screamed and hit the floor with a painful thud.

"Brilliant Harry!" Sirius exclaimed. Harry was about to reply, but before he could, saw a dark red spell hit Sirius in the chest, sending him hurling towards to veil. Time seemed to slow down in Harry's eyes as he saw Sirius arch in the air and knocked unconscious, missing the veil by a fraction of a millimetre. Sirius was struck down, by the women who was currently cackling like the mad witch that she is. Before Harry could react, strong arms circled him.

"Calm down Harry, she's not worth it." Lupin's voice spoke in his ear, but he could barely hear. His anger was getting the better of him.

"She hurt Sirius!" I'm going to kill her for it!" Before Lupin could reply, he was sent flying back by Harry's magic, no longer in control. Harry ran after her, hoping to get some revenge on her for taking his godfather. He could hearing her laughing in the distance, chanting "I killed Sirius Black!" This just made him all the more angrier as he sped up, hoping to catch her. He came to the spinning room, mixing the doors up confusing him as to which way he should go.

"I need to get to the Atrium quickly!" Harry shouted, hoping that he can catch her before she could get away. The doors span again and then stopped as a door in front of him opened. Amazed by what just happened, Harry quickly made his way to the elevator. In no time at all, he got to the Atrium and saw her sprint to one of the fireplaces of the other side.

"Crucio!" he exclaimed pointing his wand at Bellatrix's back. It found the target and sent her flying, but no screams were heard. Instead she was laughing and back on her feet.

"You call that an unforgivable boy! That was pathetic. Let me show you how it's really done. Crucio!" The spell came towards Harry at high speeds, but managed to dodge to the left.

"Accio Prophecy!" Bellatrix used the spell while Harry dodged, but no small ball came towards her. "Accio Prophecy! Accio Prophecy! ACCIO PROPHECY!" Still no small ball came zooming in the air which in turn made Harry laugh loud.

"You don't get it do you! It smashed back in the death chamber!" Harry enjoyed the look on her face turn from anger to fear.

"No! You're lying! You have to be! It's not my fault master, it's not!" Bellatrix said, with fear laced in her voice.

"What are you shouting him for? He can't hear you from here!" Harry laughed again.

"Can't I, Potter!" a cold voice said from behing. Harry turned. There, right in front of him, was the most feared man in all of the wizarding world, Lord Voldemort.

"So, you smashed the prophecy did you Potter? He speaks the truth Bellatrix, which makes me very angry indeed. How did you manage to get thwarted by a few school students? You've disappointed me for the last time Bella." Voldemort pointed his wand at her. "Avada Kedavra!" She had no chance of dodging it as it hit her square in the chest, falling backwards onto the ground. Harry looked away, he may have wanted revenge, but not to see her dead.

"Is that how you treat your servants Tom? Killing them when you don't get your way? If that's the case, you should have killed yourself a long time ago, I've defeated you four times so far, and tonight will be the fifth!" Harry spoke with as much confidence as he could muster.

"Is that so? Well then, let's see how well you do shall we, without any help," Voldemort said as he saw Dumbledore appearing from the fireplace. He quickly put up a barrier only he could break. Harry was trapped, and he knew it. Dumbledore tried to bring the barrier down, but it could not be done. Harry had to face the dark lord alone.

"We bow Harry." Voldemort bowed low and Harry reluctantly did the same. If he was going to die tonight, he was going to do down fighting. Harry and Voldemort cast their spells at the same time, the spells connecting in the middle, just like it did in the graveyard the previous year. This time however, Voldemort was prepared, breaking it off as soon as it connected and sent a cutting curse at Harry's arm, the flesh cutting from his elbow to his shoulder. Harry hissed in pain, furious with himself that he allowed Voldemort to breach his defence so early into the duel.

Harry wasn't going to give up though. Almost immediately, he countered with a stunning spell which connected with Voldemort's shield, followed up with three bone breakers in quick succession, two hitting the shield, one sneaking its way through and connecting with Voldemort's wand hand. Voldemort gave out a almighty scream as his hand looked all mangled, his wand soaring from one hand to another, continuing the duel.

Whilst this was happening, a crowd was forming in the ministry. The Minister of Magic had turned up, followed by all the aurors and the head of the DMLE, Madame Bones. Worst of all was Sirius, conscious and doing everything he could to bring the barrier down.

"Dumbledore! Help him, please! I can't lose him, not now!" Sirius practically begged of the old headmaster.

"I can't, I'm sorry, it looks like Harry is on his own." Dumbledore looked as old as ever, sadness pouring off him in waves, for what the young man in front of him as had to go through. Secretly though, he was in sheer awe as to the magic he could feel with the place. Raw magical power was radiating from the two duelist, magic crackling in the air as their duel waged on.

Voldemort was stunned at the boy in front of him. How was it that a mere 15 year old boy was able to stand toe to toe with him and match everything he threw at him. He put more power into the spells, wanting to wear the boy down enough to strike with the final blow. He saw the people in the Atrium. 'Good,' he thought to himself, 'They can see their precious golden boy fall to my power! Then they will all have to bow down to me!' He flung a killing curse at Harry, which he blocked by accio'ing a statue into the spells path, rubble blasting in each way as the spell connected.

Harry was concerned with how this duel was going. He needed to end it soon if he had any chance of getting out of here alive. Dodging killing curse after killing curse was tiring. Voldemort fired a black spell at him which he threw up a shield too. But instead of it impacting on the shield, it sucked back into him like a vacuum collecting dust. The build-up was gradually growing, until it couldn't hold no more, and came blasting back out, knocking Harry and the people outside of the barrier down to the ground. The glass from the offices all smashed, raining down on them both. Voldemort raised his arm, the glass rising up, forming a giant ball above of him, then flying back to Harry, with only one purpose in mind. Before it could do much damage, Harry raised another shield, the glass passing through, turning to sand. Harry had to look away, to avoid getting the sand in his eyes and being at an disadvantage.

Harry was growing more tired with every spell that he cast. He couldn't go on forever and he knew it. Voldemort knew it too. He had the upper hand, he could end it anytime he liked.

"You grow tired Harry, why don't you just stop now and throw down your wand, I'll make your death as painless as possible," Voldemort sneered from across the Atrium.

"Never! I will never give up to you! I will fight you with my dying breath!" Harry shot back, not about to give in to Voldemort's demands, while flinging out off the way of a killing curse.

"Then you leave me no choice Potter, Sectumsempra!" Voldemort's spell hit Harry in the lower abdomen while Harry was dodging the killing curse and Harry fell to the ground clutching at his stomach. "Expelliarmus." Harry felt his wand fly from him. He was defenceless. "Ha-Ha! Is that all you've got Potter? I was hoping you would put up a bit more of a fig…" Voldemort never got to finish that sentence. While he was talking, Harry pulled a second wand from his pocket and sent the strongest cutting curse at Voldemort. Voldemort's neck had been slashed and blood was pouring fast. Voldemort fell to the ground, gurgling, until a heave silence was heard and the barrier came down. Voldemort was dead.

"Harry!" Sirius was first in, hoping it wasn't too late to save his godson, Dumbledore right behind him. Harry was ghostly pale; a pool of blood was forming around his body.

"Professor please, save him!" Ron begged, Hermione weeping onto his shoulder at seeing her best friend in so much pain. Dumbledore started speaking the counter-curse, the cuts sowing back up, little colour coming back into his face.

Dumbledore picked up the statue head that was hit with the killing curse. "Portus!" Dumbledore whispered. "Hold on to him Sirius, it will take him to the hospital wing at Hogwarts, tell Poppy what has happened, she will help, I will come along as soon as I can. Children, crowd round and go with him, he will need you there! One… two… three." A bright blue light flashed and Sirius felt himself flying around. They were going back to Hogwarts.

That's the first chapter up. Not sure how long I want this story to be yet, probably round 20,000 – 30,000 words with it being my first one. Please review, in desperate need to improve. Till next time!