[The camera turns on and it's in night vision oo how fancy. You know Finn somehow accidentally found that setting
and never managed to turn it off and turned it back on for this very thing he's filming. And what he appears to be filming is a very, very abandoned building full of holes in every surface, broken timber, dangerously collapsed structures integral to the building's ability to remain standing--you know, the typical sort of place a ghost hunter show will go to hunt ghosts!
Which is what Finn and Terezi are doing! You can't see Finn because he's holding the camera, duh, but he's filming his gal scrambling up a particularly filthy and large pile of rubble. The camera pans in to her crazy close as he scrambles up it, too, and crashes into her.]
"Haha! Okay, found a creepy building, now what, Terezi? We don't have those weird boop-doop-boopy doohickies they use to talk to ghosts."
[Terezi stumbles forward, right into the camera's proper line of sight, and then spins around and laughs.]
"The answer is obvious, Finn!! We have to get onto the level of these so-called ghosts and draw them out by other means! Physical means."
[Boy, Zizi is so pretty all green like this! The camera tends to linger a little too much on her face, even as Finn leans down and picks up a board the proper size for whacking things. He waves it in front of the camera.]
"Like a ghost stick?"
"Uh, sure!" [But that small hesitation is glossed over as she hits her stride. Making things up on the fly is a hallmark of a good RPer!!] "Everybody knows ghost sticks are the most effective way to draw out a ghost! It is pretty much proven by movies and shit."
"The ghosts on my world are super friendly, I don't get why the ones here are all shy!" [And to help them overcome that shyness, you obviously jam a board into a large hole in the wall and thump it around, screaming:] "Come out! Come out, ghosts! I have cookies!!"
[Yes that is definitely how you lure out ghosts!! Terezi kind of smacks aimlessly at some part of the building with her cane, because that is also a tried and true ghost hunting technique!]
"Good one, Finn!! Make them think we're not going to capture them and do horrible things to them in the name of science!!"
"But I don't want to--WAIT, SHH, BRO, YOU HEAR THAT?" [He stops screaming and beating, there's a distinct scratching sound coming from his hole. He leans in very close, waving Terezi over.] "Zizi, c'mere, you hear this?"
[Terezi does indeed scramble over, and she can hear the scratching!! She slowly extends one hand toward the hole, drawing things out as dramatically as possible for Finn's sake.]
"I am not your bro, Finn! Now observe! Holes in stupid dank abandoned hives are a well-known hiding place for ghosts! I think we definitely have one here, all the signs are present."
[He pats at her mouth to shush her and leans in even closer with her, the camera showing both of them. The scritching noises coming closer, closer, Finn's eyes get bigger, bigger with awe, then--
Oh. It's just a raccoon barreling out of the hole to attack their faces.
Terezi squawks and flails in response to this unexpected attack, probably smacking Finn in the face in the process, but then she takes up her cane to try and counterattack!!
Finn was indeed smacked in the face, and down the rubble pile he falls, the camera flying out of his hand and shutting off, thus ending the first episode of the Finn and Terezi Epic Ghost Hunting Extravaganza Show. What do you think, audience?]