This is how Princess Yuna finds a book called Journal 4 and Norman goes in Welcome to Gravity Falls.
In a foggy forest with trees getting blown by the wind.
Princess Yuna: Ugh, Stan. Nobody ever believes anything I say. (puts one sign up on a tree that says "To The Mystery Shack." She starts to hammer a nail on another tree trunk, but it makes a metallic sound. She taps the tree with the hammer, which makes more metallic sounds. She wipes away some dust and opens a secret window revealing a mechanical box with two control switches on top. She tests one control but nothing happens. Then she tries the other. Behind her, a hole opens up in the ground. Gompers bleats and runs away) What the? (Looks inside the hole, and there is a book. She puts the book on the ground, and checks for people watching. She flips one page and an eye-glass is in it. She looks at the eye-glass and puts it down. She flips another page, and begins reading) "It's hard to believe it's been six years since I began studying the strange and wondrous secrets of Gravity Falls, Oregon." (Flips through pages) What is all this? (Stops at a page that says "TRUST NO ONE". Reading) "Unfortunately, my suspicions have been confirmed. I'm being watched. I must hide this book before he finds it. Remember: in Gravity Falls there is no one you can trust". (Closes Journal) No one you can trust...
Snowdrop: Yuna? Is that you?
Princess Yuna: Snowdrop, What're you doing here?
Snowdrop: What're you reading?
Princess Yuna: Let's go somewhere private.
We view The Mystery Shack. Yuna, her friends and Guardians are in the living room.
Princess Yuna: It's amazing! Stan said I was being paranoid despite that I'm a princess, but according to this book, Gravity Falls has this secret dark side since the first three journals. (Shows her friends a page)
Teslo: What's it say?
Princess Yuna: And get this! After a certain point, the pages just stop, like the guy who was writing it mysteriously disappeared.
(door bell rings)
Princess Yuna: Who is that?
Pumpkin Cake: (flips her coin) Heads!
Pound Cake: Tails! (after the coin says heads) Darn!
(door bell rings)
Pumpkin Cake: Coming! (gets the door)
EVE: (feeling puzzled)
Snowdrop: Who's here?
Princess Yuna: (sitting down and reading Journal 4)
Zeñorita Cebra: Where did you find it, Yuna?
Princess Yuna: Uh, It's a long story, Zeñorita.
Pumpkin Cake: Hey, friends! Say hello to my new boyfriend!
Norman: (turns around) 'Sup?
Tigatron: How are you?
Pumpkin Cake: We met at the cemetery. He's really deep. (Feels his arm) Oh. Little muscle there. That's...what a surprise...
Snowdrop: What's your name?
Norman: Uh... Normal... MAN!
Pumpkin Cake: He means Norman.
Pound Cake: Uh, I don't get it.
Cream Puff: Are you bleeding, Norman?
Norman: (With a red liquid dripping down his face) It's jam.
Pumpkin Cake: (Gasps) I love jam! Look. at. this!
Norman: So, you wanna go hold hands or... whatever?
Pumpkin Cake: Oh, oh my goodness. (Giggles) Don't wait up! (Runs out)
Norman: (Points at the foals and their guardians and runs into the wall several times on his way out)
Princess Yuna: (narrating) There was something about Norman that wasn't right. I decided to consult the journal.