This is called "Who's the new girl: Part 1.
(the scene shows mabel and dipper watching tiger fist)
The tv: We will return to tiger fist after this commercial.
Mabel and dipper: Whoo! That tiger is a hero!
(grunkle stan comes in)
Grunkle stan: Kids i need you to go find worthless junk for the mystery shack.
Dipper: But isn't everything in here already worthless junk?
Grunkle stan: Yes.
Mabel: Well that happened.
(they go outside)
Dipper: Ok let's look in town.
(they go to the town)
(they pass a pet store)
Mabel: Aw! Dipper, look there making puppy eyes.
Dipper: Mabel, they already have puppy eyes they're puppies.
Mabel: I know that.
Dipper: Let's go.
(they start walking till they bump into someone and the person falls)
The person: Ow! Watch where your going.
(it's a girl with long dark-red hair, and she's wearing a light-red tank-top, red boots, a dark-red short-sleeved jacket, and velvet-red shorts and a red ring that's shaped like a volcano)
The girl: Uh.
Dipper: Do you talk?
The girl: Uh.
(he reaches his hand down to help her up but when he touches her he feels heat)
Dipper: Ow! Are you ok you look hot?
(there was an uncomftorable silence)
The girl: Uh.
(she gets up and runs away)
Mabel: What was that about?
Dipper: Who knows. There's a rock grunkle stan can pass it off as a paperweight.
(he points towards a rock and goes over to it and picks it up)
Dipper: Let's get back to the shack.
(they walk back to the mystery shack and go inside to the gift shop)
Dipper: Ok grunkle stan we found you something.
(he pulls out the rock)
Grunkle stan: Thanks.
(he takes the rock out of dipper's hand and puts it on the counter and puts a half price sign on it and leaves the room)
Dipper: Mabel, i'm going to go see if i can find a monster.
Mabel: Ok dippingsauce.
Dipper: I told you not to call me that anymore.
Mabel: Sorry little dipper.
Dipper: Is this tease dipper day or something?
Mabel: I slay myself.
(the scene switches to dipper walking in the forest)
Dipper: Dippingsauce, little dipper. When will she stop?
(he keeps on talking to himself until he bumps into someone)
The person: Watch where your going.
(when dipper gets a better look at the person he realizes that it's the girl from earlier)
Dipper: You! Are you trying to follow me?!
The girl: This time i did not follow you!
Dipper: How come i just happened to bump into you in the forest! No ones in the forest! But you just happen to be standing th-!
The girl: Whoah dude slow down your talking to fast. First of all hi i'm Bella, Bella Cook and you are?
Dipper: Um....I'm dipper pines.
Bella: Nice to meet you dipper.
Dipper: Ok we know each other now but can you explain why you're in the forest.
Bella: I live here.
Dipper: What?! Let me get this straight you live in the forest???
Dipper: Then why have i never seen you before?
Bella: I'm not really supposed to tell anyone.
(Suddenly another person came out of the bushes with a bow and arrow. She Looked like Bella, but older and has black hair)
That person: Come on Bella! We need to get back to our house to- *long gasp* Bella what the hack are you doing! We have to get out of here! You know how people want to have you!?
Bella: But Jessie! He's not going to hurt us! and it's also too late! He's seen us already!
Jessie: Well too bad! You have to listen to your older sister! People are dangerous!
Bella: But we're people too! Your a normal person!
Jessie: I know I'm normal, but I have been by your side this whole time, you can trust me!?
Bella: But why do people go after me! Why not you??
Jessie: Because you were born special!
Dipper: Um... you know I'm right here!
(Jessie walks up to Dipper)
Jessie: Ugh! I totally forgot about you! You heard too much and because you heard too much I need to kill you.
(Jessie pull out her arrow and points it at Dipper)
Bella: Jessie, STOP!
Jessie: Bella! I'm keeping you safe!
Bellla: You know what will happen when I get mad, so STOP!
(Jessie looks at Bella and puts the arrow down)
Jessie: You got lucky this time kid and as for you, Bella we will talk about this later. Let's go! I've got dinner waiting for us.
(Bella and Jessie walk away)
Bella: Um... bye Dipper.
Dipper: Bye Bella!
Jessie: You told him your name!? You are in so much trouble!
(Jessie and Bella dissapear)
Dipper: Okay even if she didn't tell me her name I will still know. They said it like a hundred times and it's getting late. I better go back and I'm talking to my self.
(At the mystery shack)
Mabel: Oh hey Dipper! Thought you would be back by now. What happened?
Dipper: Ran into problems.
Mabel: What kind of problems?
Dipper: I ran into a girl.
Mabel: So? There's tons of girls in Gravity Falls. Wait, did you run into that girl that you ran into in town?
Dipper: Yeah, but I ran into her in the forest.
Mabel: That is weird.
Dipper: I mean we never run into people in the forest.
Mabel: What's her name?
Dipper: Bella and she has a sister. Her name is Jessie, but that time when Jessie tried to kill me becau-
Mabel: Waoh Waoh Waoh Waoh Waoh. She tried to kill you!?
Dipper: Long story. Anyway her sister said something about me hearing too much and how Bella had a special talent, but what could that be? I mean what is so secret that she had to kill me??
Mabel: Forget that junk. I want to go meet Ella!!!
Mabel: What ever.
(Dipper and Mabel walking in the forest)
Mabel: Dipper! Where's Bethany?!
Dipper: Bethany? Really? It's Bella!!! How did you even come up with Bethany?
Mabel: Wait, Dipper do you smell burning rock?
Mabel: Lets go check it out!
Dipper: What, but last time you said, *sigh* I'm coming.
(Dipper and Mabel crawl inside a bush and sees lava flowing on the ground. Then Bella popped out of the bushes)
Dipper: Wait bella's going to die if she steps in the lava.
(Mabel puts her hands on dipper's mouth to make him shut up)
Mabel: *loud whisper* Shhhh!!!!! We don't want our cover blown!!!!
Dipper: *loud whisper* What cover?
Mabel: *loud whisper* SHHHH!!!!!
(Bella looks around like she heard something, but shrugs and sways her arms. Then the lava starts to move in the same movements of her arms)
Bella: Haha, this is kinda fun!
(Bella keeps doing it)
Dipper: *loud whisper* What the heck!?
Mabel: *loud whisper* SHHHH!!!!!! QUIET!! I WANT TO SEE WHAT HAPPENS!!!!
Dipper: *loud whisper* Well I was quiet.
Jessie's voice: Hurry up and finish the job!!
(Bella stares at the lava and it just disapears and Jessie comes running in)
Jessie: Now the people are safe and sound. Now lets go back into the house.
Bella: Wait, no thank you and nice work?
Jessie: You only did your job. You're a rare lava person.
Bella: I saved those peoples lives and the main thing you say is that it is my job!?
Jessie: Bella don't get mad. You know what happen's when you get mad.
Bella: You made me lose my temper!! All I ever did was to make you happy! I did those training and to control my power just for you AND YOU DON'T EVEN APPRECIATE IT!!!!!!?
Jessie: Bella, take it easy. Your goi-.
Bella: ALL YOU CARE ABOUT IS HIDING AND YOUR STUPID HUNTING!!!?
Jessie: Bella, that is not true!!!
Bella: I WANT TO BE FREE!!! I WANT TO BE NORMAL!!! I HATE HAVING THIS TALENT!!!!!!?
Jessie: Calm down Bel-.
Bella: I MEAN DO YOU EVEN LOVE ME!!??
Jessie: Bella!!! You're going to CREATE A SPARK!!!!!
Bella: What oh my gosh!
(Looks at her hands and sees that lava is starting to come out of them and onto the ground, but Bella puts her hand over the lava and it flys up into her hands before it gets out of control)
Bella: *sigh* I'm sorry sis'. I just want to be normal. I mean whats so wrong with me. Do you not love me?
(Bella starts to cry)
Jessie: Of course I love you, but we have to stay safe and also save people without letting other people know.
Bella: At least can I have some alone time?
Jessie: Sure. Be back when you're done with your alone time.
(Dipper and Mabel crawl out of the bush)
Dipper: What was going on in that freak show?
Bella: Ah! Oh its just you Dipper. Did you hear the whole thing?
Dipper: Yeah and we also saw some of that lava stuff.
Bella: Wait we?
Dipper: Oh I forgot to introduce Mabel, my twin sister.
(Mabel steps out from behind Dipper)
Mabel: Hello!!!! My name is Mabel!!!! and your name is Jessie right?
Bella: Um.....no. My name is Bella. Jessie is my sister.
Mabel: Really? I never knew you had a sister!?
Bella: Um... really? I was arguing with her like the whole time.
Dipper: She's just joking.
Mabel: Got you! Haha. I'm just kidding I know all about you. Dipper talked about you the whole time.?
Dipper: Lets not get off topic here.?
Dipper: I don't want to change the subject here, but why didn't you tell me that you can create and control lava?
Bella: For the record I just create and control lava when I have to and *sigh* It's just that I didn't think I could trust you. I mean everybody was after me because of my power, so I moved to Gravity Falls, but my sister is still scared so we hide in the woods. That is why people don't know about me.
Dipper: Don't worry. You can alway trust us.
Mabel: Yeah!!!!!! Now do you want to hang out?
Bella: Um... I geuss. I mean it is better than just being alone right?
Mabel: Of course!!! That's whats friends are for!!!!
(Mabel, Dipper, and Bella walk off then the camera shifts towards this tree where Gideon was hiding this whole time.)
Gideon: Mwahahaha. Those fools don't know whats going to happen.?
(Gideon opens his book and then the camera shows the page. The page shows a spell to capture lava people and there weakness and background information.)
Part 2 is coming soon!!!!!