AN: Ugh, seriously, I have a lot of plot ideas for this fandom. This won't exceed more than 10 chapters because I usually lose interest quickly. I have a deep love for Detective AUs, and what better way to satisfy my detective-y needs than writing fanfiction!

In this AU, the Pines had a fairly normal summer in Gravity Falls, that meant that they didn't went through all of the adventures shown in the series.

Please enjoy c:

Updates will most likely be by the end of the week, either on Friday or Sunday.

Disclaimer: I do not own Gravity Falls or any of the characters mentioned below, it's rightful owner is Alex Hirsch. I only own the writing and the plot. I also don't own the cover art.


Deep Waters

She didn't have to open her eyes to tell that something was immediately wrong. She had felt it right away, a feeling of dread and uneasiness that settled in the deep core of her stomach and clawed away at her insides, she tried to push the feeling away with effort that meant nothing before giving up and simply tossing and turning on her bed until her body welcomed the silence of the night and the comfort of her bed. It never came, leaving the female to a helpless the sigh that escaped her rosy lips, turning to the side with both eyes opened as they adjusted to the barely-lit room. Red glowing letters read that it was almost time for her to get up anyways.

There was a grunt, the shuffling of blankets and footsteps that announced her awakening. Guided by instinct purely, Mabel had been heading towards the bathroom with one hand rubbing her eyes and the other combing its fingers through the messy locks of chocolate-brown hair that cascaded down her back. Yawning and stretching, she did her usual morning routine and got ready for the day, a task of at least thirty minutes that required most of her attention now a days. She looks at herself in the mirror when she's done buttoning her creme blouse and stands still as she places a single headband atop her head that matched her blouse.

Her eyes were a dark brown that held a soft shine to them and a mix maturity in them she had long acquired, barely noticeable by the prominent dark circles under her eyes, a clear symptom of being tired.

Then again, Mabel Pines had been nothing but tired and exhausted for the past few years.

After her brother and her had graduated from their high school, the twins had decided to pursue the same careers, something quite uncharacteristic of Mabel and became quite a shock to know that she would be becoming a detective much like Dipper. But alas, the years had taken a good toll on her after her boy-crazed phase and the mystery novels, the curiosity among other things, had begun to seep into her likings shortly after she had turned sixteen. She still held on to her love for crafts and glittery things, but age and experiences had changed her to be a somewhat different person, she wouldn't doubt that people would do a double take if she visited the places she had travelled.

Mabel makes the kitchen her next destination, smiles warmly when her piglet, Ziggly, oinks at her and she bends down to pet him.

The kitchen is a small space fit for one person, with old-fashioned cabinets of a maroon colour, a short island that held a couple of frames and pictures of her friends, coworkers and family. A refrigerator with various pictures from her summer album, a stove, coffee-maker, toaster and a microwave. Its comfortable enough for her to make things without having to worry about making a mess or feeling too cramped. That was one perk of living alone, the other one was that no one got to tell her how to live, after all, one would expect her space to be clean.

But from the spot she was at, brewing coffee and putting some poptarts on the toaster, Mabel was clearly aware of the mess of stack of papers that were scattered around the living room.

The thing was, being a detective was not always an easy task. Cases now-a-days were more easier to resolve than the ones from when was beginning, and at the age of 27 Mabel had become quite an expert at the job, just like Dipper had. Her brother however, had decided to move to another state to work and Mabel was more than fine with this, usually they kept in contact and would keep each other updated on what cases they had been assigned. More often than not, her cases were centered more towards normal situations, whereas Dipper's were more paranormal, something to be expected since the increase of magical creatures all around the world.

People hadn't actually been surprised by this like the twins had expected, after all, after finding both Journal 2 and 3, things had been anything but normal to them.

Still, that was the problem lately. Dipper had stopped calling a while ago, Mabel didn't pester him at all because he must've been loaded with work, just like she had been lately and in between trying to get a decent night's sleep, trying not to lash out at clients who came seeking for her help and the huge increase of paranormal cases, in which she wasn't quite skillful at, and trying to keep the Pines's reputation up as the most famous detectives in the US, sleep had stopped being a thing and she was sure that Mabel Juice wouldn't do the trick anymore.

She had switched to coffee.

When the 'ding' from the toaster registers in her ears, she blinks back into reality and trails her gaze off towards her breakfast, picks it up -ignoring just how hot it is- and chews on it, the burning doesn't quite reaches her tongue, and when she fills a cup of black coffee with too many spoons of sugar and Smile Dip, she smells it and takes a huge gulp to down the whole thing at once. She scrunches up her nose in disgust and walks towards the living room.

She's still not used to coffee, she never will, but if it's the only thing keeping her awake then so be it.

She silently prays for a smooth day today, gives her piglet his portion of food, promises him she'll be back later and then proceeds to walk out of her apartment. It's not a fancy place and the walls need repainting, and maybe the doors do too. Certainly there has to be some cleaning done as well, but the place is cheap and it's not like her job pays her more than enough to buy a luxurious house, even if she could, (she totally can) she's grown quite attached to the place, so she makes do with it. Smiles at the nice reception lady who doesn't even bat an eyelash at the brunette, and heads outside.

The day was mostly beginning, already up by seven am, Mabel decides that it's a nice day and that walking to her job would take nothing more than ten minutes if she avoids the cluster of people that become the ungodly hour of 7:30, she still doesn't quite understand why exactly at that hour people decide its a good idea to be walking around, but hey, its a different city, a whole different place from where she lived at. She had been living here for about six years, she would either have to get on with the program or be clueless as to how the city functioned.

And she did just fantastically.

She knew what each person in her apartment building did, the fights the neighbours had and the romantic affairs from the couple just above her head. She knew the time of when fights were a common occurrence, and would know when to sit down in front of the large windows that gave a clear view of the city, just to watch the group of teenagers sneaking out at school hours and play around until the police came looking for them, and oddly enough she was more than happy to know that besides all of this. The city had become quite welcoming to her, she adapter more quickly than she imagined. A bright young woman who wore too much glitter and sweaters until she turned twenty three, still kept them but her current location was too hot for her to wear them, one who would tend to people in need no matter of their status. Mabel won the heart of many people.

When she arrives at her work station, the feeling of dread doesn't quite leave and it only intensifies when she's not even done pulling out the keys to open her office when one of her coworkers, a female called Lea who wore too much lipstick and tied her long hair in a ridiculously high ponytail, tells her that another crime has been committed and that her assistance is needed, and Mabel thanks her with a tired smile and realizes that it's too early for this, and she opens her office door and clicks it shut behind her.

She needs three more minutes, another cup of coffee and more Smile Dip.


The crime scene is one that makes her face contour slightly in disgust, oddly enough the blood is scarce but the smell is powerful. Her eyes scan around the place, a shady alleyway, a somewhat cliche location to dump the body she thinks but remains silent. Her eyes scan around and she can't exactly see anything out of the ordinary, there's also a dumpster but she had already looked in there and the Crime Scene Investigation Unit had taken that as their personal job to register the place. She walks around the place, inspecting, silently.

In the middle of the alleyway stands the mangled body of the victim, The body belonged to a male of old age, somewhere around his mid-forties. His expression was one of countourned pain, one eye had been taken out of its socket and splattered against a wall. The holes in his skin were a clear sign of a messy fate, the darkened pool of blood around the body told just how long he had been left there, the way his body was filled with endless, neat holes only seemed to justify that this was done out of rage. A single shot to the head would've been all needed to end the life of the victim, but instead the killer must've wanted the victim to suffer his death.

Mabel takes a step forward, blocks out any noise from the people working around her, and examines the body closer. She's used to it by now, but it doesn't make the feeling of sadness take over her being disminue anyways, people didn't deserve to die. It still happened, she would remind herself, but it never took away the bitter feeling it left at the back of her tongue, something about it unsettled her greatly. Squinting slightly, her eyes scan over the bullet holes, each one, though scattered around randomly, had somehow made up to be perfectly lined up with each other.

"Hey, Jes, come check this out." She calls out, never taking her attention away from the victim, the male comes shortly after, her partner is a man two years younger than her, deep azure eyes with a chocolate skin that mix beautifully. Mabel likes him because he's cool to be around, and somehow reminds her of her own twin brother. "You see this, right?"

"Yeah, it was the first thing I noticed when I arrived." Jes frowns, "It's weird though, the holes are so neatly lined up it's kinda difficult to believe this wasn't planned."

"The victim wasn't tied up," Mabel states, stands up and dusts of her skirt. "You can't see any mark on his wrists or neck. Otherwise, the killer couldnt have made the holes so neatly in place."

"So, you think this was the work of a non-human?" Jes asked, crossing his arms over his chest and Mabel simply nods.

"Could be," she ponders on what she says next, "It has to be, I mean, there's no blood splatter anywhere, the victim is missing an eye and the blood around him is too perfect, you know... for it to be a blood puddle."

Something about all of this seemed familiar to her, but she can't exactly pinpoint why it is. The only good thing about her experience with magical creatures is that, because she has had limited cases with them, she can recall any certain points that could lead to know who did it. She had a vague suspicion of it being from a crime gang, those were a little bit more difficult to track down than people who work alone on committing crimes. The gangs were more organized, more clean on their work and usually marked their territory. The thing was, and Mabel knew too well, was that the territory that they were stepping on didn't show any evidence of being committed by the gang that owned the territory.

Mabel jumped a bit when her cell phone began to vibrate on her pocket, she excused herself from her partner's side and walked off towards the deep part of the alleyway, where the wall closed off any ends to the other side. Took out her cellphone and stared at the call ID, eyes widening slightly when she saw the familiar number on her cell phone screen.

The feeling from earlier morning comes back and hits her full force, and for some reason Mabel finds herself unable to answer the call, even though it keeps vibrating and vibrating. She takes a deep breath, looks around, notices the blood the seemed to become more apparent on the high walls, and her mind is filled with so many questions, How did the blood splatters get there? That wasn't supposed to be there, not when the body was so far away, it wasn't possible.

The vibration continues, Mabel picks it up without paying much attention, brings the device to her ear but doesn't pay attention to the female voice that speaks to her in a clear way that shows how desperate she is. She's too busy connecting the dots, connecting the clues she would've missed if she hadn't been receiving this call. And as the woman on the line calls her name, something in her brain clicks and her mouth goes dry, it's almost like a freezing cold has taken over her body.

It's almost instant, but she notices the splatters, four, one in front of where she's standing, two on either side of the walls in the alleyway, one at the entrance and the body in the middle lain straight, the blood underneath it forming a too perfect circle. She's snapped out of her trance when sobbing makes its way clearly into her mind, hands shaking, she knows that what she's about to hear it's not going to be good, she felt it this morning, stronger than ever. At the other line of the phone was Pacifica, her brother's fiance.

They had begun dating a while back, and it was unusual for the female to speak with Mabel through phone, rather optioning to video-chat. Hearing her voice sounding so desperate only made Mabel's sinking feeling worsen by the second. She had never heard the blonde so worried, so desperate, and her voice was barely understandable under all of the sobbing.

"Pacifica, hey- yeah- no- wait- I can't understand you." Mabel bites her lip, "Calm down, tell me what's wrong."

Her head was spinning, her eyes had been doing nothing more than going back in circles to each spot, each one becoming so clear in her brain that there was no mistaken she had seen it before. Dipper had told her he had been working on this case, for a year actually, he sent her information of the guy's way of killing, the way he worked. Neatly, precise and definitely made in a way to trick the eye.

"Oh Mabel, it's horrible-"

Maybe it was a coincidence right? Afterall, the last time she spoke to Dipper had been three weeks ago, her brother seemed fine, though the apparent lack of sleep could be heard in his voice, much like hers. She had inquired in the case, joking that possibly it was a human trying to pass off the murder as a demon (there has been cases, but they're easily told apart).

Dipper had agreed jokingly, they spoke for an amount of twenty minutes, Dipper hung up all of the sudden and she did not receive another call for two days, where he broke down and cried that he missed her and that lately he's been feeling like someones been watching him.

Mabel had deduced it was the lack of sleep, the amount of crimes going on in Dipper's section had increased in the past year and his work had been requested more than enough times to interfere with his sleep, which was really optional for him (and herself), they just liked to solve the cases As quickly as they could. She had told Pacifica to take care of Dipper and since then she hadn't been bothered with calls in plain mid-work from them.

Before the blonde could say anything else, the call ended and Mabel decided that Pacifica could wait. Afterall, she might just've been onto something here. One moment she's calling her team towards her standing spot and the next she's in her car driving towards the police station to inspect the case.


When she calls Pacifica back, she's drinking water and almost chokes on it. She cries and then sets into autopilot, she calls the meeting, organizes the paperwork and makes it into her office, buries her head on a pillow she had there in case she fell asleep sorting through papers and screams her throat raw until it hurts and she cannot believe what she was just told. She tells herself that it isn't true, and only tries to put on a certain charade so she can get this over with and not worry her coworkers.

Then she gets more coffee, black and cold and disgusting, from the coffee maker in the office, walks into the meeting room and waits for everyone else to arrive as she scans each and every photo.

She's sitting down with her legs crossed in the meeting room, tapping her fingers on the wooden surface, various photographs of the scene had been laid out before her and her investigation team, there were soft murmurs, questions being asked and information about each and every single little detail of the crime scene. So far the room had been nothing but that and Mabel listened to each and every single information being provided.

"At least we can all agree that this was done by a magical creature, everything about this case simply points to it." She chooses her words carefully.

"Yes, but the crimes committed by the magical community have decreased in a while, the way the victim was killed does not fit the MO of any of the gangs."

She had to admit that this was a certain case. Gangs and killers alike made it a point to show who's work was when it came to crimes, none of them that were around the area assigned showed the same way of killing, precisely in this way. The odd symbol that had been made with the blood splatters was one she's seen before, and the cases where those of Dipper's.

"Which is why we'll need some assistance from Ohio." She states, takes a sip from the cold coffee in front of her and says nothing when the room goes quiet, she takes it as a cue to explain and so she does.

"All of the markings, the ones made with blood, high in the walls when looked at a certain perspective form a symbol," she starts to slide each photo to the middle, forming the scene with each one of them, takes a piece of red string and begins to tie together the symbol. "and that there is the giveaway to knowing who did this."

Jes, who sees the symbol and is quick to talk, asks. "And what does going to Ohio have anything to do with this crime?"

"The suspect is not from here, that much I know." Mabel gives a simple shrug, "I mean, you all know how I have a twin brother working in Ohio, Columbus. To be more specific." She recieves a few nods. "He's been working on this case for a year, and three weeks ago went missing when he found the location of our suspect."

Eyes are widened and Mabel can't help but want to throw up. Before the meeting she had called Pacifica back after things had settled down, it took her a two full minutes of her time to tell her that Dipper had gone missing, and it took a minute for the words to finally sink in her brain, least to say, she can feel her eyes still puffy and red from the crying earlier, and the way her voice lacked her usual cheerful tone. It's not easy when you're told your twin brother is missing, and have the suspect in the case commit a crime in Seattle, nowhere near Columbus.

Mabel takes a deep breath, "The MO is exactly the same, and if my brothe- Detective Pines, has any information on the suspect, then we need to obtain this information and track down the suspect."

"So... when are we leaving?" a female voice asks, Mabel can feel all eyes on her, all of them looked at her with pitiness she'd wish she wasn't getting. Another sip from the coffee cup, the cold and bitter coffee makes do to get rid of the horrible taste at the back of her throat. Maybe she'd need more of it, less Smile Dip, more mental wellness and definitely more sleep. She knew this would be a case that would take a toll on what little grasp of reality she has after being told that Dipper had gone missing and she was more than willing to sacrifice this.

If the suspect, who by now is obviously deemed a magical entity, had done this just to call her out, then it had worked very well.

It takes Mabel a full minute to answer, and when she does, her voice lacks emotion. "Tomorrow night."


Welp, got this over with! Please rate and review! Critiques are always welcome and greatly appreciated.