Summary: When Annabeth joined Grover and Luke on a quest to England, a 17 year old wizard was not quite what she had expected to find. (Post-Hogwarts. Story starts before the events of The Lightning Thief)

A.N. So the idea of a crossover between these two series has always appealed to me and I hope you enjoy the story!

Chapter 1: We Travel to England

It had been only two weeks since Annabeth had arrived in England. She hated it instantly. The weather was awful. Monsters kept appearing every few hours. And her quest was going nowhere.

Of course in the beginning, she was really excited to go on her first quest ever since she and Luke made it to camp about five years ago. Then she realized it was just to find a demigod on another continent.

Now, the quest did not seem so exciting anymore.

Chiron had told them if they could not find the demigod in England after a month, then they should return and he would send someone else. Annabeth didn't like that. She felt that would be like giving up. But Grover had to attend some boarding school for spoiled rich kids to protect and watch over a demigod he had found earlier that year.

He seemed quite proud of the fact he was the one to find him, and was desperate to find the demigod they were searching for with enough time to return and watch the other one.

When Grover scented traces of a demigod in the heart of London. Annabeth got really excited.

They had finally made some progress on this pointless quest!

The monsters attacking them had increased in number as they neared the area. Now they got attacked every eight hours or so. It didn't take a genius to know they were pretty close.

Grover was currently sniffing the air, he seemed surprised.

"I don't understand where he went!" shouted Grover suddenly startling Annabeth. He sounded like he was panicking to her. "I swear I could smell the demigod seconds ago. And now its as though he's disappeared!"

"Maybe he is a child of the Lord of Death?" said Luke, "They can travel using shadows."

"Maybe..." said Annabeth. But she wasn't really paying attention anymore, she had been admiring the architecture of the buildings around her. Architecture had always interested her and she wanted to be an architect when she grew up. Her dream was to redesign Mount Olympus, the home of the gods.

Spotting something that intrigued her she turned to Luke, "Luke."

"What?" said Luke.

"There to your right, I'm not sure if its important but there isn't a number 12"

"A what?"

"There's no house with the number 12. 11 and 13 are right there next to each other and there's no 12."

"Maybe the people who made this place just forgot to put one," shrugged Grover. He didn't really think this was important.

"I don't think any architect could have made such a silly mistake," she replied. "Come on, lets ask someone who lives in the area."

Grover spotted a woman, probably in her forties, leaving the house that had the number 8 attached to its door. Annabeth noticed her too and calmly walked towards her, "Excuse me Madam. Can I ask you something?"

"Oh hello! Are you lost dear? You don't sound like your from around here?"

"No ma'am. Me and my friends are looking around London. I know it might seem silly. But we just wanted to ask you why there doesn't seem to be a house with the number 12 over there."

"Oh, don't worry dear thats not silly question. Besides thats not the first time someone asks me that. Well, years ago there was a number 12 somewhere around here, but I can't seem to remember what happened to it or where exactly it used to be."

"Thank you ma'am."

"Your welcome dear."

"Strange," said Annabeth after the woman had gone.

"Annabeth you think the Mist has anything to do with that happening? The mortal, she seemed confused," said Luke

"That could be a possibility, I can't think of anything else."

Moments later Grover exclaimed loudly, "Guys look I think thats him! I can suddenly smell another demigod and I'm pretty sure its him."

Looking over her shoulder, Annabeth saw a teenager that looked 17 or 16 years old though he wasn't that tall. He had messy jet black hair and as they got closer to him, she noticed he seemed to have some sort of scar on the left side of his forehead.

He didn't really pay them any attention. But she saw him glance at them out of the corner of his eyes, she noticed though he had eyes that were a striking emerald green color.

She also knew he was purposely waiting for them to come closer. Maybe he heard Grover talking about him?

He seemed a bit edgy as they got closer and he patted his pocket as if to reassure himself he hadn't lost something important to him.

When they reached him Luke was the first one to speak up, "Hey man. I'm Luke," he said while holding his hand out to him.

That was all they got to say as suddenly the teen whipped out something from his pocket.

A flash of red light was all Annabeth saw before she fell unconscious.

Harry Potter was not having a good day. Hell, he hadn't even been having a good year! After the final battle, of which he was one of the few survivors on the Light side, he felt he didn't deserve to live while his friends died.

Most of his friends had died brave deaths in the battle. Ginny, Ron, Hermione, Colin, Dennis, Seamus, Fred and countless others had all died protecting Hogwarts.

If it wasn't for Luna and Neville he didn't know how he would have survived. They had stayed with him in Grimmauld Place and comforted him.

Neville seemed to always know what to say. And Luna was great at making him feel better.

And before he knew it, three months had passed and Harry almost gotten over his friends deaths. Almost.

His life would never be the same without Ron and Hermione there beside him.

Waking up early that morning as usual, Harry decided to go for a walk before having breakfast.

Getting dressed and taking his Invisibility Cloak with him only took a couple of minutes. He decided to not wake Neville up to go with him. The poor lad hadn't been the same after he lost his grandmother and other relatives. Longbottom Manor had been attacked before the final battle.

The attack had occurred not too long after Neville had taken to hiding in the Room of Requirement. The Death Eaters must have been searching for him. They never found him, and killed the whole family instead out of frustration and anger.

Neville had predictably blamed himself for their deaths. Ginny, Ron, and Hermione, he told him, had been a big help in helping him recover.

They were used to Harry acting similarly and it didn't take long for them to make Neville feel better.

Luna meanwhile, had left to visit her father two days ago and was returning the day after tomorrow.

It wasn't long before Harry noticed the group of kids that seemed to be searching around for something.

There was a boy who he thought was fifteen, with curly brown hair and brown eyes, with white pimply skin and a limp in his walk as if he was uncomfortable.

A girl who looked around eleven years old with curly blonde hair and grey eyes.

And finally another boy with sandy hair and blue eyes he thought was fourteen or fifteen.

The fourth time he spotted them that day. He decided to use his cloak and tail them. Harry had a feeling what they were doing would interest him.

And he learned early in his life to trust his instincts. Especially when he was attacked by weird creatures. Some of them he recognized from old greek myths he'd read about when he was really young.

He passed that off as them being hostile magical creatures. He was always careful though whenever he went outside because most days he was attacked.

Anyways, when Harry put on the cloak. He started following the trio of teenagers. The closer he got the more words he could make out from their conversation.

What they said confused him.

"He must be really close, his scent is very strong now," said the boy with the limp.

"Grover you've been saying that for hours and we still haven't found him!" complained the other boy. "The most progress we made all month is when you found out he was a boy."

"Luke stop whining," the girl said scolding him, then turning towards, she asked the boy called "Grover", "How close are we?"

"I think he is...right next to us?" Harry got nervous at that. Could the Grover guy be talking about him? The boy was looking around confused. "I think I'm mixing up your scents with his. There isn't anyone near us."

Glancing at his watch as they neared 12 Grimmauld Place, Harry decided to return before Neville woke up and started worrying about him.

He took off his cloak as he entered the wards surrounding Grimmauld place. The next words he heard made him freeze.

"I don't understand where he went! I swear I could smell the demigod seconds ago. And now its as though he's disappeared!" Demigods? Who were these people?

"Luke," The blonde girl was looking right at him. Harry frowned, she shouldn't be able see him. He purposely renewed the Fidelius Charm that summer and was the current secret keeper.

"What?" said the blue eyed boy.

"There to your right, I'm not sure if its important but there isn't a number 12"

Harry sighed with relief, she obviously couldn't see him, she was just looking at the small space that was between number 11 and 13 Grimmauld Place.

"A what?"

"There's no house with the number 12 on it. 11 and 13 are right there next to each other and there's no 12 in the middle."

He watched as they talked but couldn't make out the rest of their conversation. The trio soon went to talk to a woman across the street. He assumed they were asking about the absence of 12 Grimmauld Place.

Harry badly wanted to question them, but first he had to make sure they were actually talking about him being a demigod. Maybe that was their way of saying a wizard? He made sure he had his wand in his pocket. Then stepped outside the wards.

Barely a minute had passed before Grover noticed him and told the rest of his group. They started approaching him. He patted his wand nervously hoping his plan would work.

The brown eyed boy called Luke who seemed to be the leader was the first to approach him. He noticed he had a long scar on his cheek that looked like a claw mark. "Hey man. I'm Luke," he said while holding his hand out to me.

I decided to act then quickly. I was sure they wouldn't expect anything.

I whipped out my wand. Three silent stupefy curses later and the three teens were unconscious.

Before anyone could notice I levitated them into Grimmauld Place.

The conversation I was going to have with them should be very interesting...

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Special Thanks to my Beta Reader athenaparthenos1

A.N. So this is the first chapter hope you enjoyed it. Please REVIEW and tell me what you think about it.