A/N: I know that there are more than enough Jelsa fics to go around, but this idea came to me the other day and I decided to give it a shot. Hopefully this is something that nobody has come up with so far.

Be warned: This is not gonna be your everyday Jelsa fic. There will be romance, and there will be drama, but the ending might turn out to be a sort of Shakesperean kind of thing. Just so you know.

Disclaimer: I don't own Frozen or Rise of the Guardians... sadly.

My favorite place? Hmm, that's a tough one…

Just kiddin'. That's a no-brainer, actually.

I've been all over the world, visited many wonderful places, seen the most amazing landscapes. Some of them could use a bit of white from time to time, but my powers can only do so much. After all, if I tried to bring a snowy weather to places like the Sahara or the Amazon, I would probably cause an irreversible disaster on a global scale. Or not. I'd rather not find out anytime soon. Don't ask me how, but I just know that I must not mess with the world's natural balance, or the consequences would be quite unpleasant.

Hey, I told you not to ask me how!

But anyway, I'm getting a bit off track. My favorite place, without a doubt, is Burgess, a small town in Pennsylvania, USA. Why? Well, there are plenty of reasons. I was born and raised there before I became a spirit. I was reborn there. I became a Guardian in that place. And of course, my best friend and first believer lives there. His name is Jamie, and he is one exceptional kid.

My name is Jack Frost, Winter Spirit and Guardian of Fun. And today is the first day of winter.

Now, the science of it is really boring, but if you must know, winter officially begins in the Northern Hemisphere during the winter solstice—not counting the regions beyond the Arctic Circle where I've already introduced winter a month ago—which occurs at a specific time, not just day. This means that in order to introduce winter, I have to fly around the Earth at a speed of about… man, I don't know. Real fast, I think? It's more or less like what Superman did in that 70s film, except that I don't travel back in time.

At least I have the advantage of being a spirit. It makes things a lot easier, as a regular human wouldn't survive traveling at such speed. Thankfully, I only have to do it every once in a while during the next three months. That leaves me with enough spare time to bring fun—and have fun—in certain places where and when it's needed… and sometimes where and when it isn't.

What can I say? I'm a prankster at heart.

Anyway, tomorrow I'll visit Jamie. The kid probably could use a good snowball fight.

I arrive at Burgess at midday and find Jamie sitting at the porch of his house, his head resting on his hands and his rather soft gaze lost into the void. I feel tempted to throw a snowball at him, but then I think of something else to let him know that I'm here. I land as carefully and quietly as possible behind him.

"Somebody looks really dreamy," I say, making him jump.

"Jack!" he says, spinning around to give me a tight hug.

"Hey, kiddo," I reply, returning the hug. "How're you doin'?"

"I'm great. How about you?"

"Oh, you know," I say, letting go of him and holding my staff behind my neck with both hands. "Having lots of fun here and there. Now, will you tell me why you're acting like a happy zombie today?"

Jamie doesn't answer. He just sighs, smiling.

I think I know what's going on here. It's been 4 years since I became a Guardian, and Jamie is now 14. That means puberty, hormonal changes, and whatnot. And…

"What's her name?" I ask teasingly, smirking.

"Karin," he replies without hesitation, sighing again.

I rarely see this kind of stuff happen during winter. It's supposed to happen more often during spring—though I'm still to understand how a lonely sourpuss like Bunny manages to do that when he brings summer along with Easter—but I guess it can occur at any time of the year. I bet he thinks this Karin girl is and will be his one and only true love. Any boy that's fallen in love at that age believes that, or at least boys with a heart like Jamie's. I wouldn't want to break it by telling him otherwise, even though most of the times it's true.

Well, he was the first one to believe in me. I guess I should believe in him too and hope for the best. Who knows? There are a few marriages that started as a couple at a very young age. Maybe Jamie and his… friend could be among those few.

"You have to meet her older sister!" Jamie exclaims all of a sudden, interrupting my train of thought. "I'm sure she'll like you, and you two would make such a—"

"Whoa, hold on a second. When did the subject change from Karin to Karin's sister?"

"Just now," he replies naturally.

I laugh at his childish antics. This kid could grow old and never stop having a child's heart. They say that children stop believing in us Guardians at a certain age, but I don't think Jamie will. In fact, his friends have all stopped seeing me by now, while he still does. There must be some exceptions to that rule.

"I appreciate your effort to make me meet a girl, Jamie, but you know that older kids and teenagers can't see me."

"She just might if you help me convince her. You could throw her one of your magical snowballs and—"

"Convince her?" I chuckle. "Who am I, Pitch Black? I can't force her to believe. And even if she did believe, I'm not really interested in a relationship of that kind." I fear my reply has been a bit blunt.

"What? Are you telling me you've never been in love?"

"Never in my 300 years as the Winter Spirit," I say proudly.

Jamie seems shocked by my answer, but the reason is pretty simple. I spent most of those 300 years worrying more about being seen by everyone than only by a single person whom I would've outlived anyway. And now that I'm a Guardian, I still think of it that way, though at least most children can see me now.

"Come on, Jack. At least humor me and come with me today to Karin's so you can meet them both."

I sigh and raise my hands in defeat. "I guess I can do that. But only if you and I have a really good snowball fight with them later on."

"Deal."

About two hours later, Jamie and I are standing at Karin's porch. The nameplate at the side of the door reads 'The Vinters'. That's not a very common surname in America. I look at Jamie and raise an eyebrow.

"Her family just moved in from Europe," he shrugs.

He knocks somewhat shyly. While we wait, I give him a gentle shove in the shoulder.

"Hey, relax," I tell him, trying to calm him down. "You're just going skating to the lake. It's not like you're getting married today or something like that."

"Married?!" he squeals.

Ups. Not exactly the intended effect.

"You get my point," I tell him with a wink.

The door opens, and a cute brunette girl with hazel eyes and a smile that Tooth would love to see from up close greets Jamie with a peck on the cheek. He blushes a bit. Then she looks at me, and her jaw drops.

"Jack Frost?"

I furrow my brow. This doesn't happen very often, even though kids have been seeing me more easily since I became a Guardian—and even then, they need to see my work first, such as a good snow day or snowballs appearing out of nowhere. Besides, she must already be at the age limit in which regular children still can see us.

"You are Jack Frost!" the girl exclaims. "Jamie has told me so much about you!"

I turn to Jamie with slightly narrowed eyes.

"I… may have told her about my adventure with you and the Guardians," he says.

"Of course you did," I reply teasingly.

"Oh, my sister's gonna want to meet you!" the girl says. "I'll leave her a note to join us at the lake when she returns."

And before I can react to what she's just said, she runs back into the house. Jamie and I look at each other, puzzled.

What just happened? First Jamie, and now his friend? What could possibly make them believe that a teenager might see me?

Karin returns within the minute and literally drags Jamie away from the house and towards the road that leads to the lake. I trail closely behind and watch them as they start talking and laughing. Once we arrive, they take some time to put on their skates. I can't help a smile while I hear them chatting. From what I've been listening so far, Karin sounds like she has the heart of a true believer, just like Jamie. They may be for one another, after all.

"They look lovely together," a feminine voice says behind me. "Then again, which couple of kids doesn't look cute at that age?"

I turn around, a bit startled, and find myself staring into a pair of ice blue eyes belonging to a young girl with pale skin and long platinum blonde hair tied up in a ponytail behind her back. And she looks strikingly beautiful…

Wait. Where did that come from?

I quickly push the thought aside. There's no point in trying to start a conversation with a gorgeous girl who can't—

"What? Is there a bug in my face or something?"

I feel my heart skip a beat. There's no one else around us, and she spoke directly at me. In fact, she doesn't seem to be looking through me at all.

"You… you can see me?" I ask disbelievingly.

"Of course I can. Why wouldn't I?" the girl replies with a smile.

This girl can see me! But how? Aside from Jamie, no person older than twelve or thirteen has ever seen me. What makes this girl so special… so different?

"Who are you?" I wonder out loud.

"Oh, sorry. I'm Lizette. Nice to meet you, Jack," she replies, offering her hand.

My bafflement only grows. "How do you…" know my name? I intend to ask, but then I remember that Karin left a note for her sister in which she probably also wrote my name, so I guess that this girl must be Karin's sister.

That doesn't change the fact that this teenager can see me. How in the world can she see me?

"Wow. Jack Frost is speechless. That has to be a first."

What?!

"Don't worry," she says, lowering her hand. She doesn't seem offended by my rudeness of not accepting it. "You'll be talking with fluidity again in no time, once things are clear enough for you."

She winks at me and runs off towards the lake, leaving me utterly stunned. What. Just. Happened?!

"Hey!" Lizette calls out to me. "Aren't you the Guardian of Fun? 'Cause you seem rather dull right now."

I snap out of it to see her skating gracefully along with the kids. When did she put her skates on? I suppose I've even lost all sense of time and that I've been standing like a fool for a while. She has promised me that things will become clear for me soon enough. Maybe I should trust her? But in any case, she's just challenged me, and that's something that I can't let pass, no matter how confused I may be right now. My fun side takes over, and I lift off from the ground, flying above the lake.

I make it snow a little to add a bit of winter charm to this moment. Then I look down—and watch in horror as Lizette suddenly trips and falls, causing the ice to crack. Jamie and Karin freeze in place, and even from so up high, I can see the look of terror in their faces.

I fly down as fast as I can. I already save my sister from drowning once, and I didn't even have the power that I have now. I have to save those kids.

I break my fall roughly ten feet from the ground and get in an upright position in order to land gently on my feet and fill the cracks with ice to make the lake surface solid again…

…but before my toes can even touch the shattering ice, the cracks disappear.

"Whoa, that was close. Thanks, Jack!" Jamie says, his terrified expression fading away almost instantly.

I nod, though I know that I can't take the credit for this. I look at Lizette who is still on the ground and offer her my hand to help her stand—and I don't fail to notice that her fingertips are touching the ice in a… sort of peculiar way. She takes my hand…

And then I know.

I can sense it.

She has ice powers like me.

My eyes widen while she gives me a soft smile and a shrug.

Who is she, indeed?

A/N: Rather short chapter, I know, but this is just the prologue. And in case you're wondering, no, that's most certainly not Elsa.

If you feel just as confused as Jack was, don't worry. Things will be clear for you all too in Chapter 2. Now, don't panic if it takes me about a month to upload it. I'm a bit focused with my other Frozen crossover right now, but I will be updating this story every once in a while until I finish that other fic, and then I'll start updating this one more regularly.

Don't forget to review on your way out!