So I got a little into the Rise of the Guardians film (Isn't Jack Frost awesome? XD) and I figured I'd do a little crossover with Harry Potter, featuring Alex of course. Anywho, I'll have to warn you guys that this is majorly AU, due to the following reasons:

- Alex's presence in the story affects it that much already

- Sirius, Fred, Remus and Tonks don't die (I love them too much)

- The battle begun at sixth year, so you can disregard the Half-Blood Prince. (I need to do this to satisfy the ages so Harry's year mates are mostly 17 or 18, Harry and Alex are both 17)

So I hope you guys enjoy the story! If you need to know more about Alex, check out my story "The Slytherin Side of Things".

Disclaimer: I don't own Harry Potter; it all belongs to J.K Rowling and Warner Brothers Inc, and Rise of the Guardians belong to DreamWorks. However, I do own Alex.

One would think that everything would be fine, now that the final battle was over. Hogwarts had been fully repaired and was ready for the start of term, old and new students returning to finish their education; all the rogue Death Eaters captured and placed in Azkaban. Above all, Voldemort was gone, and everyone could just move on with their lives. Most of them have, just not her. Alex Potter leaned against against the tree trunk, gazing at the Black Lake. It had always helped her think.

She was one of the many that had returned to Hogwarts for their Seventh Year, but only one of the few Slytherins that did. With her were Draco Malfoy, Blaise Zabini, Theodore Nott, Pansy Parkinson, Millicent Bulstrode, Tracey Davies, and the Greengrass sisters: Daphne and Astoria.

Alex sighed and closed her eyes, letting the wind blow her hair back. Despite everything, she felt something wasn't right. Perhaps she was just worried. Her brother, Harry, and his best friend, Ron, chose not to return this year and became Aurors whilst Hermione had chosen to resume her studies. But both of them were tough; they had survived a war after all, so she had no reason to worry about them. However, the churning in her gut told her that something was coming, something big . . .

All of a sudden, the temperature dropped, and the wind picked up. Alex's eyes snapped open and she stood, her wand sliding from its holster and into her awaiting hand. She watched anxiously as the lake slowly froze over, and the air chilled. Dementors? Alex frowned, awaiting the onslaught of horrid memories. Oddly enough, nothing happened.

"What - ?" she began, when someone came floating down, landing on the now-frozen lake. It was a boy with snowy white hair, striking blue eyes, and pale skin, and wore a a blue hooded sweater, frost collecting around the ring of the collar, and trousers bound with lighter material starting from the knee down to the rather tattered and frayed bottom. He also carried a crooked, shepherd's staff. What was strange though, is how he stood on solid ice, yet he was barefooted. Didn't his feet feel the cold?

There was that feeling in her gut again. On instinct, she pointed her ebony wand in his direction and fired a stunner, and the boy barely dodged it, the jet of red light whizzing just by his head as he turned to stare at her with wide eyes.

Alex glared at him in suspicion, "Who are you?"

Jack Frost sighed. Even after today, Jamie merely passed through him. It was a hollow, empty feeling that made his stomach drop. A snow day, an awesome sleigh ride, but no one believed in him. Was it too much to ask for someone to be able to hear him? To see him? Three hundred years alone was painful; people just came and went, not knowing he even existed. Jack settled himself on the roof of the Bennett house, staring up at the moon.

"If there's something I'm doing wrong, could you tell me what it is? Because I've tried everything, and no one ever sees me." Jack leaned on his staff, his hood up. "You put me here. The least you can do is tell me…tell me why?"

The moon shone brightly, like he was smiling for some odd reason. Then, a voice whispered in his head . . .

"Hogwarts... Go to Hogwarts..."

Jack blinked. Hogwarts... He had been there every Christmas of his existence to bring snow to the place. It was a school, he had noted, but the students and teachers there seemed... different somehow. He didn't know why they were, but he never stuck around long enough to figure it out. Most of the students were at the start of their teen years, and probably didn't believe in him. So why bother getting his hopes up?

He glanced at the moon again, "It's a long way, but I'll give it a shot." he called out, "Wind, take me to Hogwarts!"

It was mid-day when he had reached the place, and the newly rebuilt castle came into view. Jack laughed, freezing over the lake as he passed. It wasn't time for winter yet, but he couldn't resist. Through the ice, he could distinctly see large creatures swimming at the bottom of the lake. Wow, those fishes were huge!

He grinned as his feet settled on the cool, solid ice, looking up just to see a flash of red light head straight for him. He dodged, the light whizzing passed his head as he looked towards his attacker in surprise.

It was a girl, not older than he was, with long jet black hair and bright green eyes. She wore a black robe over her white button up, a green and silver tie peeking through, a dark pleated skirt, and a pair of black stockings and dress shoes. She held up a small wooden stick, pointing it right at him.

Finally her pretty little features settled into a glare, "Who are you?"

Jack didn't answer straight away, he was focused on something else. This girl could see him! She - She was talking to him! It was almost too good to be true, even if she did try to blast him off the ice.

"Can - Can you see me?" Jack spoke hesitantly as he approached her. The girl's grip on the wooden stick tightened, and she eyed him cautiously.

"Yes. Shouldn't I be able to?" said the girl.

He got excited for a moment but then stopped, and then asked, "You can hear me?" The girl nodded again. The happiness and excitement flooded him tenfold, and he yelled out, "She can see me?! SHE CAN SEE ME!" He did a backflip and landed in mid-air, "WHOO-HOO!"

Jack then landed in front of her, a large grin on his face.

The girl stared at him oddly, then lowered her hand, "Well, you're definitely not a Dementor. So, who are you?"

"I'm Jack. Jack Frost." Jack held out his hand to her, the one that wasn't holding his staff, watching as the girl's eyes widened a fraction.

"Are you really? You're nothing at all like I pictured." she took his hand, which Jack noted was warm compared to his own, and gave him a hesitant smile, "I'm Alex Potter."

This boy was strange, Alex decided. It was hard to believe this was Jack Frost. Muggles pictured him as an old man who brought snow and blizzards wherever he went. This boy didn't look much older than her, but he definitely looked like a winter spirit. His hand was cold to the touch, and she shivered a tad at the sudden temperature drop before releasing it.

Then, she asked, "Why were you asking if I could see you?" Alex immediately regretted it when his expression fell.

"No one's been able to see or hear me for three hundred years."

"Three hundred years?" she sputtered in shock, "That's awful! You must have been very lonely."

"You have no idea." Jack replied dryly. "Only people who believe in me can see me. So why can you? Usually teenagers don't believe in all that fantasy."

Alex snorted, "Well, when you've seen and battled Centaurs, trolls, and giant snakes, you'll believe just about anything."

Jack raised an eyebrow at this, "Have you?"

"You have no idea." Alex smirked as she stepped away from him, and turned to trudge back up the castle. "I'll see you some other time. I have classes to attend." she called back.

Jack watched her retreating form with a smile on his face. His first believer in three hundred years, and it felt brilliant, no matter how strange the girl may be.

I know it wasn't very good, but I hope you guys enjoyed it! Please review and tell me what you think!

~Cassandra