Chapter 1: Bright Lights, New World

A/N: Alright, so here it is! This is my first Gravity Falls fic, and it does include two OC's. Just to give a little bit of a backstory, the two OC's are sisters, one 17 and one 12, who have moved to Gravity Falls and befriended the twins and landed themselves jobs at the Mystery Shack. Bill is also a part of their group, having accidentally trapped himself inside a human body. He and Eve, the older sister, also have a bit of a chemistry between them, but a relationship with a demon would be a little more than complicated so i'll leave the little thing they have without a name to really classify it.

I suppose this could be considered an AU what with the added characters and backstory, but everything else remains the same.

Now, without further ado, on with the story!

o00o

"Quick, it's still behind us!"

Dipper panted as his arms pumped furiously at his sides, willing his breath to stay in harmony with his strides. The bushes around him licked and scraped at his bare legs, causing tiny droplets of blood to trickle down the flesh.

But he was too preoccupied to pay any attention to that.

"Dipper, wait! We can't all run as fast as you!" Phoebe wheezed, slowly falling behind. The boy immediately noticed this and stopped to grab her wrist before resuming their mad dash, pulling the brunette along with him. Eve and Mabel followed suit, not far behind. Bill had tried to give them enough time to get a good running start by distracting the monster and teasing it with his blue flames.

The whole endeavor began as a normal mystery hunt, like they always did.

Dipper had become obsessed with a new page in the journal and was hell-bent on finding the creature that was drawn there and described in crude penmanship. The others wouldn't let him go alone, for fear of something happening and because they were all at least a little curious to get a look at the monster. They'd had a whole plan well thought-out ahead of time, complete with cautiousness and the perfect trap. But of course this all lifted away the minute the group of teens was faced with the creature.

Instead, they all screamed and bolted the other way.

The adrenaline coursing through his veins coupled with the passing branches that hung low in his path impaired Dipper's vision, causing him to completely miss the root protruding out from the ground.

"Dipper watch out!"

"Oof!"

He stumbled, and the journal went flying.

"No!" He reached out for it, but it was too late. Dipper stood up, dumfounded, staring at the strange circle of swirling orange light that the journal had just vanished through.

"What the-"

"Hey! Why'd you stop? It's gaining!" Phoebe panted, gripping the boy's shoulders for support. The others came to a quick stop as well, their questioning glances soon turning to marvel at the same light.

"What is that?" Eve asked, wide mocha eyes shining with wonder and slight fear.

"I don't know, but the journal just fell right through it!"

"It looks like a portal to me," Bill answered, looking back over his shoulder. He guessed they had about twenty seconds before the beast caught up with them and had them for supper.

Mabel cocked her head to the side. "A portal to where?"

"I don't know, and I don't care. I'm not sticking around here any longer! I don't wanna be gremloblin meat!" Phoebe said, nearing the portal with determined strides. Before anyone could get another word out she jumped through it, disappearing from sight.

"Phoebe!" Eve shrieked with panic, quick to follow after her sister.

Protective side kicking in, Bill chased after Eve and disappeared as well.

"Oh boy. This could be very very bad," Dipper worried, before Mabel grabbed his wrist and he found himself being dragged towards the portal.

"C'mon Dipper! We've gotta get out of here!"

The twins squinted their eyes and held their breath as they were pulled into a new world of unknown things.

o00o

"Ugh, my head…Man, what a ride." Eve rubbed at her throbbing skull and groaned lightly. A dull light filtered through her eyelids, and she cracked them open a bit to get a look at where they were. Strangely enough, she was met with the same trees and sky she was familiar with, if not a little less vibrant. But then, it could just be cloudy. There was nothing odd about this.

Oh, but there was.

Why would there be a portal in the middle of the woods that didn't lead anywhere? It didn't make sense, and was all-too suspicious.

Eve sat up slowly, relief settling some of her nerves once she saw everyone had made it through okay and were also sluggishly pulling themselves off the ground.

"Hey guys…where are we?" Phoebe asked.

"It looks like the same place." Mabel said, looking up at the trees and thick forest around them. "Minus the gremloblin."

Bill said nothing, completely silent as he stood up and took in their surroundings. His eyes scanned the area furiously and cautiously, something about the place giving him a twisting feeling in his gut.

Something wasn't right here.

"Wait…" Dipper's eyes widened as he suddenly began to whip his head about, panic rising inside him. He scrambled up, clutching his hair in his hands. "Where's the journal?"

"You mean this journal?"

"Dip, quit talking to yourself. It's…weird…" Mabel trailed off as she turned around and caught eyes with a familiar face.

Except he wasn't familiar at all.

Instead of warm, shining brown orbs, she was met with ice cold ones that were hard and held a certain hatred in them. This boy's brown hair was neatly slicked back, revealing the constellation imprinted there on the skin of his forehead. He was dressed almost formally it seemed, with his blue button-down tucked into black dress pants, paired with a long cape that gracefully draped over his shoulders. The most curious thing however was the bright blue pendant settled in the middle of his neck, holding the cape closed around him. It seemed oddly familiar...

"Oh, it's weird alright." The boy said, voice just as similar as his looks were to a certain male twin. And he was holding the journal in his hands.

The others gaped incredulously at the abomination before them, eyes flashing from the brunette in the vest and shorts to the less casually dressed one.

"Dipper…why are there two of you?" Eve whispered, panic clear in her tone.

"I-I don't know," he responded, matching the other Dipper's eyes in a wary and unsure staring contest.

"Enough games." He snarled suddenly, eyes flashing dangerously. "What are you? Shape shifters? Trying to take the form of someone in power to gain a little, are you?"

"What? No!" Phoebe waved her hands defensively. He turned his steely gaze on her the instant she let the words escape, and she found herself feeling strangely squirmish under it. It wasn't like Dipper's normal loving look. No, the way he stared at her now was different…darker. "We…we're not shape-shifters. We were running through the forest and fell into a portal. Now...here's a question for you. Why do you look like Dipper?"

The boy narrowed his eyes and placed his hands on his hips, standing tall in attempted intimidation. "I am Dipper."

"No, I'm Dipper! Now give me back my journal!" He reached for it, but his counterpart easily held it back away from his grasp.

"Journal…you mean this tattered old thing? It looks about ready to fall apart." He said with a snort and flipped it open carelessly, eyes roaming a random page. They suddenly grew darker as he scanned over more pages, flipping through them furiously until he finally slammed the book shut. Without looking up, the other Dipper spoke in a voice so low that he nearly growled. "Where did you get this?"

"It belongs to him," Eve barked, refusing to be intimidated by a twelve year-old duplicate of the boy.

"Does it now?" A smirk pulled at the corner of his lips as he pulled the journal flush against him. "I beg to differ."

"Hand it over short stack, and no one gets hurt," Bill ordered, tone equally as harsh as the boy's and leaving no room for argument. Sometimes it helped to have a demon on your side.

The counterpart seemed caught off-guard by this, expression completely surprised until it shifted into that of rage. "How dare you speak to me that way!" He barked, fists clenching at his sides.

"How dare I?" Bill parroted, a few amused chuckles escaping him at the child's words. "You're a riot kid! Seriously!"

"Keep in mind who you're talking to, demon." The boy said through grit teeth, venom dripping from his words. "You don't want to have to face the wrath of Dipper Gleeful!"

"Wait, what?" Phoebe spluttered, eyebrows coming together in confusion. "Gleeful?"

Bill's irritated demeanor slowly began to vanish, leaving behind a clear expression of realization, bright yellow eyes filled with understanding. "I know where we are."

"Really? Where?" Eve asked while still keeping a cautious eye on the other Dipper.

"We've stepped into a parallel universe, one of the many ones there are. It's commonly referred to as The Land of Backwards Reality."

"Backwards reality? What does that mean?" Dipper wondered, while his counterpart only watched the exchange with scheming eyes. He was just as curious as the rest to find out what was going on.

"Basically, everything that's normal in our world is the opposite here. Black is white, white is black, good is evil, and evil is good." Bill explained, using his hands to demonstrate a sort of scale gesture.

The other Dipper hummed lightly, skimming his fingers over the cover of the journal. "Interesting…very interesting. I suppose that must make you the weak ones." A small smirk tugged at the corner of his lips.

"Weak ones?" Eve scoffed, a deep frown etched onto her face as she pointed a finger at his chest. "Watch it buddy!"

"Is that all you've got?" He asked, genuinely expecting a better retaliation. The others stayed quiet, glaring at the boy. He chuckled lightly and momentarily inspected his nails. "My my, this is embarrassing. Oh, Mabel and the others will certainly want to hear about this."

"Hey hey hey, you're not going anywhere, bucko! Not until we figure th-"

"Not to worry." The counterpart said, abruptly cutting off Mabel's sentence, leaving the girl to huff and crossed her arms. "I have a feeling we'll be seeing each other again very soon. Until then!"

Before anyone could utter a single word of protest counterpart-Dipper raised his arm and smashed something down on the ground, his entire figure was quickly enveloped by some kind of thick black smoke. The group of teens coughed and wheezed as the substance entered their nostrils, the scent sickening. After a few moments of holding their noses and waving it away, the smoke eventually cleared to reveal…nothing.

Dipper gasped.

His counterpart was gone.

o00o

Town looked different.

The sidewalks were cracked and chipped, and the buildings on either side of the street looked old and worn-down. The townspeople didn't walk along happy and oblivious like they normally did. In fact, there weren't many people on the street at all. The occasional person that did walk by held a strange and uneasy aura about them, keeping to themselves and glancing around every few seconds as if they had just committed an offense and were afraid of being caught.

The group looked like a vibrant abomination in the dull world they'd found themselves in, and a couple times they'd caught suspicious or even fearful glances towards them. Though no one could see their faces due to the hoodies Bill insisted were necessary. He'd said that since they didn't know what kind of reputations their counterparts held it would be better to stay hidden and not have anyone recognize them.

"This place is weird," Eve said, wrapping her arms around her torso and hugging herself tightly. "I don't like it."

"It's not that bad," Mabel scoffed. "Besides Dipper's obnoxiously snobby counterpart."

"Hey, you could have the same attitude for all we know," her brother argued, eyes suddenly catching a familiar figure across the street. "Whoa, is that…Tyler?"

The man was walking out of an abandoned-looking shop. Then again, they all looked like that. His shoulders were sunken and so was his face, but the thing that stood out most to the group was his attire. Namely the large panther that stretched out across his front.

"Wait a minute, he actually chose a shirt?" Phoebe gaped, before her expression twisted into one of worry and fear and she found herself having to look away. "You're right Eves, this place is weird."

"Look, we've established we want to spend as little time here as possible, alright? But we have to get the journal back first."

"Pine Tree's right, as much as it hurts to agree with him. If this universe's versions of you start using our journal here, it'll tip the balance and both universes will crash. Now we don't exactly want that to happen, so we'll just need to get the journal from them and then jump back through the portal."

"Right. Piece of cake then." Phoebe barked lightly, rolling her eyes.

"It's the only plan we've got, Pheebs," Eve said, placing her hand on her sister's shoulder.

The girl sighed. "I know, I'm sorry. I guess I'm just a little on edge. I mean, did you see the way he looked at me? Creepsville, I tell ya."

"It's okay. We'll be out of here soon. We just have to figure out where other-me took the journal." Dipper said, eyes roaming the dead street. "Look, Greasy's! Maybe Lazy Suzan can help us."

"Oo!" Mabel chirped, face brightening. "And maybe we can get some pancakes while we're at it!"

She was met with a few questioning looks, but the girl only threw her hands in the air innocently. "What? We can't very well steal the journal back on empty stomachs, can we?"

Bill gave an exasperated sigh.

Eve only shrugged. "Worth a shot."