Disclaimer: I don't own any of the known characters or places in this fic, sadly.

(Warning: Long author's note ahead. It's not crucial to read however I do recommend it so you have more of an idea about what you will be reading. It's just a brief, not so brief, overview of what will be happening in 'Under the Hood'.

Welcome to my Harry Potter/Arrow crossover and thanks for checking it out and giving it a chance. This is the my first fic but hopefully that won't make a difference and you'll all still enjoy it. I've been working on this for a while and have got the first of many chapters already written out and have only just had the courage to actually put it up anywhere.

Anyway, this as you've probably figured out is a crossover between the Harry Potter universe and the Arrow universe, where Harry was caught on the island with Oliver and they both start Oliver's crusade together. I know this had already been done a couple of times already but I thought I'd give it a try, and it's my aim to make it completely different from the ones already up and the Arrow series itself. Yes there are going to be the same story lines as the show but as there is another character in it, one who is younger and can do magic to a certain degree, a lot of things are going to change. Or at least, that's what I plan on.

This is a story on Harry so all of the scenes/parts/chapters or whatever you want to call them, will be on him and have him in. Sadly this does mean there will be a little less of Oliver as he won't appear in everything, after all Harry is in his late teens now and isn't going to follow Oliver around all the time, otherwise I personally think they'd both get sick of each other. There will still be a lot of Oliver though as well as Tommy, Laurel, Thea, Felicity, Dig and so on. There will also be some appearances of characters from the Harry Potter universe, especially Ron and Hermione as they were previously a big part in Harry's life before the island. There will also be other characters from Harry Potter appearing in it, although I'm not certain on who yet.

The Harry Potter universe, although not where the fic is mainly set will be different. Voldemort will no longer be a major threat, if any threat at all as Harry has missed out on five years of Hogwarts, so therefore things there will have changed course from what we know and Voldemort hasn't come into power again yet.

Final thing before you can read, unless you skipped over this, is how this will be set out. I'm definitely going to be having flashbacks included in this and they too will be slightly different, although not as much as everything else, and I'm planning on doing three to four chapters per episode, apart from the prologue. I'm also going to be putting additional episodes in it that I've come up with myself as I feel this will make it more interesting and clear up any gaps that might appear from changes to the TV show.

Anyway, I'm done now so if you're still with me I'll let you read what you came here to read. If you read all of this then congratulations because this is like the longest authors note I've ever written.

Under the Hood

Prologue:
The beginning

5 Years Ago

The recently turned twelve year old sat in the back of the car staring out of the window as cars and buildings went by. The boy had emerald green eyes behind a pair of black rimmed glasses and a thick mop of black hair that stood up on all ends like he had just crawled out of bed.

The truth was the twelve year old had already been up for several hours, thanks to his cousins constant moaning and tantrum that he'd pulled earlier on that morning. It had all been in an attempt to get his own way but it hadn't worked due to the stubbornness of the adults, the twelve year olds Aunt and Uncle. They couldn't leave their nephew at home alone in America. That was unthinkable. However, it wasn't because the wanted him with them, no that was unthinkable too. In his aunt and uncles mind Harry Potter was not to be trusted anywhere alone. As if leaving him alone would cause the house to blow up.

Harry fought back the bitter laugh that wanted to form at the thought of that. So far nothing like that had happened. Not that it would be a big loss if it did.

The worst thing that had happened in a long time was his cousin, a great lump of a boy, getting trapped in a snake enclosure at London Zoo. And that had been a mistake. It had happened a year ago, in the last summer holidays. Again harry fought back a laugh. This time at the image of his cousin, a bully and a spoilt brat, banging on the glass cage of the enclosure panicking and screaming to get out. The previous inhabitant, a snake longer than Harry himself, sliding away, hissing a thanks to the twelve year old as it went.

Harry would never forget the shock that went through him when he understood the language. In fact that wasn't the only thing strange about Harry. There were several things strange about Harry. The first was hidden under his hair, a lightning bolt scar on his forehead. The scar, although twelve years old, still looked fresh and was a constant reminder of what he had lost when he was a baby.

His parents.

The second and strangest thing about Harry was his other life, the one that terrified his remaining family. Harry potter was born a wizard and he went to a school where he learnt to control his magic, only coming home in the holidays. He'd found out about this on his eleventh birthday, the same day he had found out the true reason for his parents death. And he'd been told this by a giant, well, a half giant but still, he'd met a giant.

A dark wizard, called Voldemort, had killed Harry's parents when he was a baby and had tried to kill Harry too. He had failed though, bringing himself near death instead as the spell backfired. The only thing that Harry had been left with was the scar on his head, it was the only thing that proved he was there and made him so well recognised in the wizarding world. He'd become known as 'The boy who lived' a celebrity in the wizarding world. It was Voldemort who had ruined Harry's life forcing him to live with his Aunt, Uncle and cousin. The only living relatives he had left and the people who hated him most.

"Hey boy!" Harry's uncle, Vernon Dursley, snapped bringing Harry from his thoughts. Harry turned to look at Vernon, ignoring the lack of his name that came from the man's mouth. He was used to it. In the years Harry had lived with them they had hardly used his name. He could probably count on his hands the number of times they had used his name."Were you listening?" the man said again getting angrier by the second.

"Yes" Harry said back evenly. "you were telling me to behave and stay out of site. No funny business. Stay in my room." It was a complete lie. He hadn't been listening but he didn't need to to know what his uncle was telling him. His uncle had been repeating himself the last couple days and Harry knew exactly what the man was saying now because of it. And if he got something wrong or added more than Vernon had said, oh well, the man wouldn't care as long as Harry stayed out of the way. Harry knew he had been correct when he saw the man glare at him through the front mirror of the car. Obviously and clearly annoyed that Harry was right.

"Well then I expect you to do just that. If you ruin this for us Potter..." The sentence was left unfinished as Vernon concentrated on where he was going. Harry already knew the answer, a week back in his old room, the cupboard under the stairs with the smallest of food to go with it. This didn't bother Harry. He was glad to be out of there and he could probably manage to stop his uncle from going through with the threat too. All he'd have to do was threaten the man with magic instead. When Harry had come back at the beginning of the summer holidays he had chosen to leave out the part about not being allowed to use magic out of school. Watching the family draw pale when he mentioned magic was great enough, but watching his cousin squirm in fear and hold his bottom whenever he mentioned it as well was even better. It was too great an opportunity to give up so quickly.

Besides in a few weeks time Harry would be going back to Hogwarts and he wouldn't see them for just under another year. He would be with his two best friends, Ron and Hermione, and be in the place he preferred to call home. For now though, he was in America and would be spending his time there on a yacht and he would at least try to enjoy it like Hermione had told him too.

The company that Harry's uncle worked for, Grunnings, a drill company, had recently started working with a company overseas in America called Queens Consolidated. Harry didn't know much about the company other than the fact that it was owned by a billionaire who lived in Starling City. Vernon had been going on about them for weeks, mostly about their money, and then last week told them he had been picked to travel to America to make a deal in China along with Queens Consolidated. His employer had told him that if the deal was a success, and Vernon believed it would be, then Grunnings would be bringing in a lot more money, which meant bigger pay checks for the workers. Especially the one who had made the deal in the first place. It was their 'big break' if Harry had heard the man correctly. However, Harry knew by 'their' Vernon actually meant himself, his wife and his child. Harry wouldn't be included in that matter.

As if to prove Harry's thought his uncle said, "This is our big break." As the car pulled to a stop at a port overlooking the sea the man started sorting out his tie, trying to flatten it down against his enormous stomach. This was a much harder task though as it just curved around the fat on his waist. Giving up Vernon turned and looked at the occupants of the car. "Remember what I said, be polite and welcoming. If this is a success it will change our lives. Petunia you already know what you're doing" he said giving his wife a smile who returned it reassuringly herself. He turned from his wife and look at Dudley. "Dudley remember please and thank you, first impressions are the key in this. And Harry" the man said almost spitting out the twelve year olds name. "stay quiet. The less you talk the more of a chance we have at this deal going our way."

Harry hid the frown on his face by looking out at the sea ahead of him. He knew the true reason was because the family were terrified the Queen family would find out about Harry's magic. Find out that the Dursley family weren't as normal as they liked to make out they were.

The Dursley's got out of the car leaving Harry alone for a few moments. As he went to open the car door it swung open and Harry was met with his uncle whose face was turning a dark shade of red than what was his normal skin tone. Quickly Harry climbed out of the car and slung his back pack over one shoulder before turning to face the car and making himself look more presentable in the reflection of the car window.

Looking at himself now, Harry realised he looked tidier than he could ever remember. He knew the reason for that too. He was no longer wearing his cousin's old and far too large clothes. His Aunt Petunia had taken him out shopping on Sunday to buy new clothes. He had bought several sets of clothes, that weren't cheap either as his Aunt wanted Harry to look his best too and realised that wasn't going to happen in cheap second hand clothing. At the moment Harry was wearing a pair of black jeans with black trainers. He also wore a blue top with a checked shirt over the top of it. He looked reasonably presentable, even with his hair still being a mess. There would never come a day where Harry would be able to control his hair. The back pack he had was also new, something he had managed to get out of his Aunt after saying he needed to keep his personal things somewhere. She had snapped back something along the lines of 'what personal things?' but bought him a black sports bag anyway.

Inside of it he had kept a few of his things from England. It wasn't much but it was all he needed. There was a picture of him and his friends from last year right before they left to go back home. It was taken by Hermione whilst they were on the Hogwarts express so all three of them were still in their uniforms. There was also a red hoodie thrown in at the bottom of it and pieces of cake that he had smuggled out of his bedroom after his friends had sent him them for his birthday.

Hearing voices behind him Harry turned around to see his uncle shaking hands with a tall man in his late forties. His hair was a pale brown receding and he wore smart but casual clothes that showed Harry that the man was used to doing this sort of thing. For the third time that day he was struggling to hold back his laughter. His uncle, aunt, and cousin were dressed as if they were going out for a meal, Vernon wearing a suite and Petunia wearing a dress that looked like she'd come back from having a meal with a celebrity. Out of the four of them Harry was the one that looked like he fitted in the most as he was wearing casual clothing that suited the heat outside.

He walked over to join the group of four and stood behind them, doing what his uncle said by staying out of site. "It's good to meet you Mr Dursley" the man said.

"It's good to meet you too Mr Queen" replied Vernon shaking the man's hand one last time before letting go. "I'm looking forward to working with you." Harry listened to the conversation unable to see what was going on. He was surprised his uncle could suddenly sound so welcoming and kind instead of the usual grumpiness that seemed to be his only mood when they were back in England.

"As am I" Robert Queen said. "And this must be your family." The man smiled warmly at Dudley and Petunia, missing Harry who was hidden behind them.

"Yes this is my wife Petunia and my son Dudley" Vernon said still keeping up the calm and happy manner.

"It's good to meet you too Mrs Dursley."

"Please cool me Petunia" Mrs Dursley said back. Mr Queen smiled as an answer and then turned to Dudley.

"Good to meet you Dudley" he said holding out his hand to Dudley who shook it.

"You too Sir" Dudley said as politely as he could.

"Come on. You can call me Robert. We're all friends here. What about your other boy Mr Dursley, you said there were four of you coming?"

Vernon hesitated for a slight second. "Err, yes, but he's my nephew, we took him in when his parents died. Harry!" he called calmly. The man looked around and saw Harry standing behind them. "Dudley move over so Harry can fit in."

Dudley scowled at his dad and then moved over a fraction to give Harry just enough space to stand between his aunt and cousin. "Hello Harry" Mr Queen said again holding out his hand for Harry to shake. Harry did and the man carried on. "Im Robert Queen but you can call me Robert."

"Harry Potter" he said.

"Well Mr Potter, you seem to be the one that has the most sense in your family when it comes to wearing practical clothing" the man joked and Harry found himself smiling at it although a part of him wished the other man hadn't mentioned it. That was one easy way to annoy his aunt and uncle.

"Yes… he… erm. He refused to wear anything else" said Mr Dursley trying to cover up his mistake.

Mr Queen laughed at that, his laugh warm, "I was only joking. How about we go inside and I'll show you around. Then you can get changed into something cooler."

"Yes that would be great" said Mr Dursley following the man as he walked towards the yacht. Harry followed next to Dudley who was purposefully knocking into him as they went. At one point Dudley managed to push Harry forwards without anyone noticing and then stuck his foot out for Harry to trip over. Harry felt himself fall forwards but stopped when he went into someone knocking them backwards as well.

Harry quickly stood back and looked up at the young man with blonde hair. "I'm sorry I wasn't looking where I was going." The man looked at Dudley then at him, having clearly seen Harry being pushed into him.

"That was me, sorry, I wasn't paying attention. I'm Oliver Queen" the man said.

Harry was about to reply when he heard his own name being shouted behind him. "Harry, watch where you're going" Vernon shouted pulling Harry away a little roughly. "I'm so sorry Mr Queen. My nephew never pays attention to what is going on around him." Harry looked away knowing that his face would clearly show that he was angry if someone saw it. Harry didn't notice the look shared between the two Queen's and neither did the other family.

"It's no problem really Mr…" Oliver hesitated to let the man say his name.

"Dursley, Vernon Dursley" Mr Dursley said.

"Well Mr Dursley. Like I said there's no problem. I walked into him." Oliver looked to Harry and gave him an encouraging smile.

"Yes well, he still should have been paying more attention" Mr Dursley said still trying to cover up for Harry.

"We can forget about. I'll keep an eye out on where I'm going in the future and you can keep an eye on both of your sons." Oliver didn't try and hide the emphasise he put on the word 'both'. Proving that he had definitely seen Dudley push and trip Harry.

His dad gave him a pointed look which Oliver shrugged at. He then said, "Is there something you wanted Oliver?" his dad asked trying to change the conversation,

"Yes" the younger man said. "Did Sara arrive whilst I was gone?"

"No she hasn't but if you checked that you had everything with you this morning you wouldn't have had to go back home to pick up the things you forgot."

Oliver let out a huff of laughter at that. "I went through most of it this morning. Just not the things I left behind."

"Of course you did. Just be careful with Sara otherwise it won't end well with Laurel." Harry saw Vernon and Petunia share a disgusted face with each other before he turned his attention back to the Queen's.

"I will be. Could you let me know if you see her?"

"Yes" Robert said and Oliver nodded his thanks before leaving again. The Dursley's followed Robert onto the yacht, this time with the two adults separating the twelve year olds. When Harry was shown where he would be staying, which was on the same floor as the other living quarters, he decided to stay there to get away from the Dursley's.

-o-0-o-

Within the next hour the boat had left the port and was sailing out at sea. Harry hadn't even noticed until the noise from land that he had gotten used to start to disappear until there was only the sound of waves against the boat. But that was three days ago and in that time he had spent the majority of his time in his room. It was a lot nicer than his own one back in England but not as big, but then again he was on a yacht so how could it be. Now he sat on his bed drawing in a notebook that he'd stolen from Dudley. The other boy hadn't noticed, he couldn't even remember getting it last year for his birthday but Harry still kept it hidden as he knew Dudley would take any opportunity he could to get Harry into trouble with his parents.

Harry looked up from the notepad when he heard his uncle's voice down the corridor from his room. Looking down at his watch Harry realised he'd been in his room for the best part of the day. The white clouds of the morning had vanished from the sky and had been replaced by dark grey ones. His uncle got closer to his room and Harry could just about hear his uncle's voice and Dudley whining back to him. He put down the notebook and headed over to his door so that he could hear what was being said clearer, being careful with how much noise he was making. Even from behind the door Harry had to strain his ears to hear over the constant tapping of the rain on the boat, he hadn't looked outside his window but he knew what the view would show.

Dark clouds in the sky meeting with a dark ocean at the horizon.

This didn't bother him though as he was planning on spending as much time as possible in his room but he knew his uncle, aunt and cousin would be annoyed by the change in weather so he wasn't going to complain. He leant closer to the door wishing he could use magic outside of school and use a spell to block out all the other noises around him. His wand was in his bedside cabinet, even though he knew he wouldn't need it he had still decided to bring it with him to the yacht, hiding it from his Uncle when the man locked his school things in the cupboard under the stairs. That included all of his homework. He had already come up with the start of a plan to get his uncle to let him have his things again, as he knew that his uncle would do his best to avoid letting Harry have any of it until he went back to school at the end of the holidays.

"I know Dudley but we have to" Harry heard his uncle say to Dudley.

"No we don't. He always ruins everything. He didn't have to come." Dudley's whining voice was louder than his dad's and Harry heard the older man 'shh' his son. "He ruins everything!"

Willing for his hearing to suddenly intensify Harry pushed his ear further against the door crack. He knew his cousin and uncle were still there and he wanted to hear the rest of the conversation. Unlike his cousin Harry had an unnaturally large sense of curiosity that he usually couldn't keep hidden and at bay. This had been shown on several occasions. Especially last year at Hogwarts. Because of his curiosity he and his two friends had uncovered the truth about their defence against the dark arts teacher, realising that he was trying to steal the philosophers stone. A stone that could offer the elixir of life. Obviously at first Harry had believed it to be his potions teacher who planned on stealing the stone. But according to Hagrid, the half giant, that was because the two had a mutual hatred for each other.

It was his curiosity that seemed to get him into the most trouble at school.

The hushed moaning from the other side of the door brought Harry back to the present and he resisted the need to bang his head against the wall. Obviously, in the short time Harry had been lost in his own thoughts, Dudley had gotten no further to getting his own way so had turned to his last and final tactic. Pretending to get upset. Instead Harry rolled his eyes to the ceiling, still concentrating on the conversation in front of him.

Uncle Vernon, sensing the oncoming tantrum that was slowly building up started to talk to Dudley very quickly. "When we're done here we can go away for a week back home. I just need you to show the Queens what a delightful boy you are okay." Dudley sniffed in reply.

"I don't like them, his son was horrible to me. Thinks I tripped"-

"I don't like them either alright. And as for his son, just ignore him, the man doesn't have enough brain cells to even think about accusing you of anything." Harry raised an eyebrow even though no one could see him. From what he had seen of the Queen family so far they didn't seem to be bad people and he was almost certain that his uncle had mistaken Dudley for Oliver Queen.

Without notice the door to Harry's room opened giving Harry only just enough time to pull away without getting hit by it. Uncle Vernon's eyes drew together into a scowl. "What were you doing?" he asked.

"Nothing" Harry said. Seeing his Uncle still looked suspicious he explained further. "I thought I heard you call my name."

His uncle still looked at him disbelievingly but Harry ignored it trying his best to look innocent of eaves dropping. "Yes well I didn't. Get up to the top of the boat in five minutes. Mr Queen wants everyone there to have dinner as a group." Uncle Vernon left before Harry could answer muttering to himself in anger as he went.

Harry was sure he heard the sentence 'but of course his idiotic son doesn't have to come' before he left the hallway. "Okay" Harry said to himself as he closed his door and headed back to his bed. Pulling out his back pack from underneath the bed Harry quickly unzipped it and pulled out the red jacket from the bottom, not noticing the small photo come with it. He then pulled it on over his head and put the notepad back in the bag before zipping it up and sliding it back where he'd got it from. This time however, Harry did notice the photo and picked it up pocketing it as he didn't have time to go back and put it in his bag.

As he opened the door to his room he hesitated and looked back at the bedside cabinet draw where he knew his wand was waiting, hidden under his spare clothing. For a slight moment he thought about going back and picking it up before coming to a conclusion and leaving it behind. After all, how much trouble could he actually get in without it? He was only going to have a meal, nothing bad would happen.

He left the room not realising how badly he'd need his wand. Harry grabbed the side of the hallway wall as the floor of the boat beneath him gave a massive lurch sending him off balance. He steadied himself and looked to see if there was anyone else around that seemed to notice the sudden movement. The twelve year old had to stop halfway through this though as the boat made another sudden jerk causing Harry to this time stumble and fall onto his hands and knees only just keeping his glasses on his head. As he looked up he saw water coming towards him.