Dipper laid back down across his mattress, staring up at the wooden rafters. He watched the lazy light from the window as it illuminated the room. The light bounced off of the dust particles in the air, casting a warm glow.

It was a late Saturday morning, and Dipper was resting alone in the attic. His twin was downstairs watching a High School Musical marathon on TV. Mabel had made it her goal to binge watch all three of the movies over the course of the summer, and she had taken up today to do it. The echoing chorus of "Get Your Head in the Game" could be heard throughout the shack with Mabel's voice getting lost in its sound.

"Blugh," Dipper thought out loud. Mabel had tried to stiff arm him into the movie too, but Dipper refused. She was disappointed, but agreed to let him go without much fuss. Sure, Dipper was out of bargaining glitter, but it was worth it. By the seventh time around, not even the upbeat "We're all in this together" can save High School Musical from being a monotonous repetition. Stan had disappeared a little earlier that morning, taking the paper and a cup of coffee with him. Now Dipper laid alone on his bed, staring blankly up at the ceiling. He only wished that he had thought of something to do before dismissing himself from the movie.

Dipper inhaled, and blew at the tuft of hair resting across his forehead.

Suddenly sitting up and stepping off the bed, Dipper reached beneath the frame to grab a wooden box. The old wood screeched as it dragged along the floor. Inside, Dipper's journal was laid flat across the bottom, along with a small black light and a multitude slightly chewed pens.

"What do you have in store for me today," Dipper muttered as he turned on the black light. He held it in one hand while he flipped through the pages with the other. He paged through the familiar pages, smiling at the parts he noticed as his own additions. The Gnomes, the Hide Behind, and the Gobble Wonker; all familiar passages Dipper had all but memorized.

Dipper stopped mid-flip, feeling the page pinched between his fingers. This one felt heavier than the others- and almost stockier.

Placing down the black light, Dipper leaned closer to the page. Sure enough, this paper was thicker than the rest. In fact, it almost looked as if two of the pages got stuck together.

"No way," Dipper disbelievingly said under his breath.

Rubbing his two fingers holding the page in place in opposite directions, Dipper watched as the two pages began to separate. As the papers fluttered apart, Dipper released a breath he didn't realize he was holding. With two new pages laid out in front of him, Dipper leaned in close to them. One was relatively blank, containing only a few lines of a paragraph that had been blotched out with ink. The other page was only half completed. Both were covered in yellowed glue, which had split when Dipper separated the pages.

A small excerpt was in the corner of the legible page. It was accompanied with a small sketch of a creek, dotted with large insects and other small creatures. The writing beneath the glue was smeared.

While mapping out the layout of the woods, I've discovered an unusual body of water. The Fluvius Cantatis, as I've decided to call it, flows between two ponds deep in the forest, located in the Northeastern corner of the woods (see section 3). Appearing to be nested in a relatively quiet location, it is a favorite watering hole for many of the magical beings living in Gravity Falls. The creatures that surround it do not seem to mind my audience, which makes it an excellent vantage point for observing the magical creatures' behavior. I was unable to approach the water being that the creatures around the shore seem unnaturally inclined to protect it. However, there seems to be several phases in the day that creatures tend to leave it uninhabited. Perhaps because of a ritual of some sort, but I was unable to prove this theory.

There was a second inscription below the first in a different pen.

WARNING: Keep Your Distance In The Dark: More Hostile Creatures Inhabit The Area At Night!

Dipper grinned wildly as he read the paragraph. It didn't seem dangerous, at least not by Gravity Fall's standards, and by looking the map, didn't seem too far a hike from the Mystery Shack. Grabbing his backpack from the bedpost, he slung the bag over his shoulder and proceeded down the stairs, journal in hand.

Mabel peeked over from the top of the couch as Dipper emerged from the staircase. She rested her chin on the wooden frame.

"Hey Dipper! Change your mind about the movie?" She grinned brightly, showing off her braces.

"'fraid not," Dipper replied, crinkling his nose. He turned towards Mabel as he walked towards the kitchen door. "How's your movie?" Mabel inhaled deeply, perking up as she did so.

"Good! I forgot how good these movies are! You're really missing out Dipper."

Dipper smiled inwardly as Mabel recalled the Disney drama. She nearly had these movies memorized from watching them over and over back on rainy days in Piedmont.

"So..." Mabel twisted herself around so that she hung upside-down off the couch. "Where are you going Dips?"

"A creek." Dipper stated. Mabel stuck out her tongue.

"Just a creek?" She questioned, hanging from her knees now. "Or is it a bit more..." she paused, lowering her voice dramatically. "Sinister?"

Dipper shrugged.

"Maybe. Sounds like it's a cool place to check out- there might even be some magical aspect to it." Dipper paused. "I might even get to see some monster in their 'Natural habitat."" He finished, adding air quotes around natural habitat. "I mean, I don't think magic counts as anything natural, but…" Dipper ended in a shrug. Mabel hung there for a moment, looking deep in thought.

"Huh. Is that one of the pages you added?"

Looking down, Dipper realized he walked down the stairs with the book open. It hung with the newly discovered pages pointed towards Mabel. He rushed over, showing the page to his sister.

"Actually, no. Mabel, you won't believe this,"" Dipper beamed. He turned the book, showing it to Mabel. "I was flipping through the pages and found these two glued together- I mean, look at it! It's incredible!" Mabel squinted and grabbed for the journal. Pulling it from Dipper's hands, she slid off the couch, landing in a headstand like slouch.

"You just found these pages?" Mabel exclaimed. "You've had your head buried in this book for weeks!"

"I know!" Dipper enthusiastically replied.

Mabel looked back at the book, squinting intensely at the illustration.

"Did you see these pixies?"

"What?" Dipper crouched over his sister. He leaned in close to the page, getting a better look at the illustration. Sure enough, the human-like creatures he mistook for insects all had long, spindly legs and arms, all sporting different poses. They all had wings, ranging from insect-like, bird-like, to even a pair with thin, leathery bat-like wings.

"Fairies…" Dipper breathed, gazing at the small creatures.

"That's it," Mabel announced, jumping up and racing for the stairs.

"What's it?"

"I'm coming with!" Mabel yelled back. Her voice was muffled by the floor now between them and the sound of her hurried footsteps along the wooden planks. "No way am I missing out on pixies and fairies!"

"I thought you were watching a movie!" Dipper yelled up at the ceiling.

Mabel appeared at the bottom of the stairs, now wearing a pink sweater. A large fish was colorfully stitched across it. A small backpack had also been slung across her back.

"Dipper. There's fairies out there." Mabel pointed dramatically out the window facing the woods. "I don't think I need to say more than that. Besides, you'll need a lady guide to introduce you." She smiled, grabbing his hand and heading out the door. "This is so exciting! What if we find a unicorn! They're like fairies, right?"

"No, they're over hyped horses." Dipper explained, only halfheartedly attempting to pull away from his sister's grasp.

"Pbbt, don't kid yourself- I know you've read Fablehaven. They're basically the same thing!"

"Mabel, that's fiction."

"You're fiction."

"I thought you said it wasn't that far." Mabel thought aloud, pulling herself over a fallen tree.

"I guess I'm not as good at map reading as I thought I was," Dipper answered as he crawled under the log behind Mabel.

Wet dirt was sticking to Dipper's knees. Lifting up his hands, Dipper grimaced at the wet mush clumped on his fingertips. "Ugh." He groaned, wiping his hands on a nearby tree stump. The temperature was a little warmer than comfortable, and the air was sticky from days of rain in the past week. Despite this, it was a relatively nice day. The noon sun was high in the sky, and the clouds dotted across it were just enough to keep the sun off the twins back. The trees also provided ample shade from the beating sun.

"Come on slow poke!" Mabel called. She leaned dramatically along an oak tree up ahead. Dipper pushed away from the tree trunk and ran towards his sister. He stopped beside Mabel, sliding forward in the mud.

"No!" Dipper panicked, wrapping his arms around a tree for support.

"Smooth!" Mabel giggled, skidding up to him.

"Neh." Dipper complained. He was shakily trying to regain his footing. "I feel dirty."

"Well, you are covered butt to toes in mud." Mabel commented. "And I thought waddles was the pig around here."

"Har-de-har." Dipper deadpanned.

"Aw, lighten up mud-butt." Mabel laughed, skipping away with a spray of mud. "It's just a little dirt." Dipper rolled his eyes.

"Just a little dirt," Dipper mimicked, steadily making his way through the underbrush. "And bugs and ticks." Mabel simply laughed in reply.

Dipper sighed and parted a pair of bushes. He paused, then turned his head back.

"Hey Mabel." Dipper called.

"Yes, Sargent party pooper?"

"Come look at this."

Mabel leaped forward to look over her brother's shoulder.

"Whoa," she breathed.

A large creek ran across the clearing in front of the two twins. Water ebbed several feet from its submerged banks while still pools of mud surrounded the lazy stream. A partially buried oak lay toppled over across the water.

"Where'd all this water come from?" Mabel wondered aloud.

"It must be from all the rain, "Dipper speculated. "I thought I read somewhere floods were more common during winter, but summers probably just as vulnerable."

Dipper gazed thoughtfully at the center of the water. Beneath the Oak, the current swirled where the rest of the barely flowing. He pointed to it. "Mabel does that look weird to you?"

"The water? Pbbt. What it's going to do, magically sink us?" She wriggled her fingers. "Ohohoo."

"No, Mabel. I'm serious. Doesn't that rub you the wrong way?"

"Please, Dipper," Mabel argued. "It's just water." She grinned. "Here."

She bent over, pulling off her sneaker.

"Mabel, what are you doing?"

"Proving a point." Tossing her shoe aside, Mabel dipped her toe into the waters.

"Mabel, be careful!" Dipper shrieked. He reached for Mabel's arm. She yanked away before Dipper grasped her. "Get out of the flood water."

"Dipper, try and loosen up a little. What on earth could happen?" Mabel yanked of her other shoe and tossed to the shore. Then she wriggled her bare toes in the mud. "See? Perfectly safe."

"Mabel, get out of there. Do you know how bad that water could be? It could be full of chemicals or sewage." Dipper hissed.

"I'm fine, Dips. Stop being such a spoil sport. I'm not going to go and do something dumb."

"Alright… Just stay away from the weird current." Mabel scoffed in reply and danced away from her twin. Dipper huffed in defeat, sitting down on a fallen log nearby. Mabel twirled in the waters, sending up sprays in multiple directions. Dipper grinned. She always stayed within a hop of shore and as far away from the swirling vortex as possible. Feeling satisfied with himself, Dipper gazed up at the sky.

Then Dipper frowned. He didn't know when it happened, but dark grey clouds had consumed the sun from view.

I guess we didn't notice from under all the trees. He thought to himself. And are those- Dipper recoiled as a drop of water pecked his cheek. Raindrops?

"Mabel, we should head back." Dipper called, cautiously hopping down from his perch. "It's starting to rain." Mabel paused mid twirl, gazing up at the sky.

"Alright," She called, jumping to shore. She slid forward a bit more than she meant to, brushing against her brother. "Whoops! My bad."

"Don't worry about it." Dipper grinned. Then he fell silent. His face contorted, like he was focusing on something.

"Dipper…?"

"Shh." Dipper waved his arm, silencing his twin. "Do you hear that?"

The soft sound of rushing water could be heard off in the distance. It rapidly grew louder, gaining accompanying sounds of woods and metal as it continued.

Both sibling's heads snapped toward the sound of breaking wood. Then the water around rose in a matter of seconds, till it lapped at their waists.

"Flash Flood!" Dipper shrieked, wrapping his arms around Mabel just as the final push of water came crashing through the tree line. Mabel secured her arms around her brother as the waters started pulling them with the current. It quickly carried them further and further downstream.

We're going to die, Dipper thought, panicked. He twisted wildly to find a way to get loose of the current. Mabel stared back at him with the same scared expression. Her hair swirled madly in the water, making it hard to see which direction was which. He met her gaze, before his eyes darted toward a looming shadow above the water. An overhang! Dipper realized.

Turning toward Mabel, he motioned for her to hold onto his waist. She looked at him in horror, as if to say "What do you think I'm doing?!"

Then Dipper let go, paddling wildly towards the rock. Mabel quickly tightened her grip on her twin, burying her fingers into his sides.

With the overhang approaching fast, Dipper had to kick widely to reach it in time. He stopped paddling just in front of the formation. He collided with it harshly a second later. Dipper scrambled to quickly dig his fingers into the grooves of the stone. He felt his feet shoot up from the force of the current, banging painfully against the rock.

"Oh no," he murmured, a little too late. He felt Mabel's grip loosen as she hit the rock. Then the presence of her arms curled around his legs completely disappeared. He peered over the rock just in time to see Mabel's form sink into the murky depths.

"Mabel!"