First fanfiction for either of these fandoms, and I think this is my first written crossover for anything too! :D

Disclaimer: Do I look brilliant to you? Well, there you go. I don't own these characters. This story idea was (obviously and accidentally) strongly based off of The Little Mermaid, though that story line and history will be changed quite a bit from that movie/story. Seriously, it's just the 'saved by a fish' and 'not happy with where I live' theme that's Little Mermaid-like.

I made the story's picture myself using four pictures I found on the internet: Jack Frost and Hiccup (obviously), some shirtless model (nice abs, dude.), and water. I layered and colored them, using a program I have on my computer. Just in case you wanted to know...

Enjoy! :D

Very, very slowly… Hiccup stood, as well as he could. His feet felt unstable in the stirrups now that he wasn't seated firmly on Toothless, but that was part of the fun. His blood rushed. He spread his arms out, and closed his eyes, feeling the warm sun and breathing the wind in. Free. There was no other word for this feeling he had whenever he flew this high, or this far. He didn't belong to anywhere or anyone or anything but his dragon, and he wouldn't till they landed.

Lowering himself again, he leaned down so that his face was as close as he could get it to Toothless'. "You ready?" After getting the trill of affirmation, Hiccup patted Toothless' neck and straightened. First, he switched the appropriate gears to give Toothless full control of his tail, and had him test it out. It worked beautifully. And after over a year of failed tests (and life-threatening crashes when Toothless forgot something) it should.

Next, he unhooked his safety belt, and tried to relax. "Okay." The idea was really simple; Hiccup jumps off Toothless, Toothless flies after Hiccup, Toothless catches Hiccup, Hiccup puts the safety belt back on, they fly back to Berk, and Hiccup invents a new adrenaline-pumping stunt for next week. Piece of cake. Yeah.

Hiccup jumped. This was the great part. Toothless was still flying straight… maybe slightly downward and Hiccup was face-first headed to the ocean. He was far enough up in the air still that death didn't really feel that close at all, and he had complete confidence that Toothless was going to swoop down any moment and catch him.

But then he didn't. Toothless turned around like he was supposed to, and flew toward him, but when he tried to grab him, he missed. He flew right past, and Hiccup was falling further. Toothless tried again, but he missed again, too. Hiccup could feel the panic rising. The water was closer, and Toothless was getting more frantic with his reaches. He couldn't hear him telling him to fly under and break his fall, but was now just flying straight down toward him, forgetting the zig-zag approach.

Hiccup was facing up now, staring at Toothless barreling toward him. It was strange- in the back of his mind, Hiccup was reminded of just a couple years ago, when he was falling to fire instead of water, and Toothless was chasing after him just the same way. This time, though, there was no 'we just saved our people', it was just 'we should have practiced this more'. He knew he was so close to the water, just from an estimation of time, and Toothless' increased panic. He also knew that once he hit it, Toothless would know to not go in after him; the prosthetic he was wearing wasn't waterproof, which is something he really should have thought about and fixed before this.

All that thought happened only in a second, because he was closer than he thought; he hit the water, and everything was white, then black.

The next moment Hiccup was aware of, he was shooting to a sitting position, taking in such huge gasps it hurt his throat. His lungs and chest felt heavy but empty, and his head was throbbing. He held his chest, holding where the weight had been. Before he had time to take in where he was, there was a large splash in the water just by him.

He scrambled to the edge of the rock and leaned over, just in time to see what had made the splash. There was something swimming down into the sea. All Hiccup could see was a giant tale, like a fish's; it shone a silver-blue and stretched longer than human's legs, and at the end there were fins, a deep blue, but nearly transparent. But in a less than a second, the whole being was gone.

"HICCUP!"

"HIIIICCUUUUP!"

"HICC-UP!"

Every man and woman who had a dragon and no little ones to look after were out looking for Hiccup. Astrid heard all the voices calling for Hiccup, and as often as he could get on everyone's nerves, she was comforted to see how many people still cared enough to join the search. Of course, if they didn't, Stoic would probably have more than words with them. But still, the more help they had the better.

Hiccup had been gone since early morning with Toothless, before most vikings were even awake. The sun was just rising when Toothless came back alone and panicked, riling all the other dragons up too. The riders were mounted immediately, she and Stoic before anyone else. Stoic was leading his search group East, and Gobber was looking West, and she had South, toward the sun, where Hiccup usually flew in the morning. Panic swelled in her gut; it wasn't often that a missing person was found. And she didn't know if the fact that he wasn't on a boat made his survival more or less likely.

It took twenty minutes of flying over water for Astrid to finally find him, sitting alone on a set of black rocks, completely wet and shivering, staring ahead at nothing.

After landing, she jumped off Stormfly and dropped next to him, taking his freezing face in her hands. "Hiccup?" He looked at her but not quite, lost in nothing she could see. He looked like he was sleeping with his eyes open. "Hiccup! Can you hear me?!" She was near screaming, and she moved her hands to his shoulders and shook him hard. His head jolted back and forth before finally snapping up.

"Astrid?" She squinted at her in confusion. "What- what are you doing here?"

"What-! Rescuing you, Hiccup. Are you alright? How do you feel? You're freezing!"

"I'm fine, Astrid. I – there was this… thing in the water, and she-" he stopped and frowned, while Astrid tried to get him on his feet. "-he… it…. It was beautiful. I've never seen anything like it, so – so magical! It had a – a tail like a fish but it was so giant and more like a…. I've been thinking about it, and it could only be a siren."

"Hiccup!" Hiccup stopped when Astrid yelled again, still dazed as before, but shocked at her unexpected outburst. "Hiccup, you're not okay right now, I think you're delirious and probably in shock. I'm going to get you back with the rest of the group and then we can see how you're doing. I'm sure you just saw something in the water that looked like a siren."

He let her help him onto her dragon, but still protested her words. "No, I didn't imagine it, I'm sure. It had a blue tail." He said that like it was his proof that he was right. "It wasn't there for long, but it was very clear, even though I couldn't see well. My eyes were burning 'cause of- 'cause of the water."

"Sure, Hiccup." She could pretend to believe him for now, if that would keep him quiet. She climbed behind him and took Stormfly's reigns, wrapping one arm around Hiccup as the started to fly. She squeezed her eyes shut, trying to not think over what Hiccup had said 'til later. Imagining a siren here was crazy, and she could only hope that he wouldn't remember any of this later.

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Thanks!

-tofs