Mabel and Soos make exclamations of awe.

"What the?" Soos looked around.

Mabel gasped, "Whoa, this is Stan's mind?"

"I figured there would be more hot old ladies," Soos shrugged.

Mabel sighed, "Remember everyone, we've got to look out for the triangle guy."

Bill , arriving, "Yeah, look out for the triangle guy!"

Soos shouts, "It's him! It's the guy!"

"You leave our uncle's brain alone, you isosceles monster! Gotcha! Wait, what?" Mabel looks at him in confusion.

Bill laughs, "Ah, Stan's family, we meet at last! Question Mark, Shooting Star, Pine Tree, I had a hunch I might bump into you!" He shoots a hole into Dipper's chest.

Dipper screams, deep breathing.

Mabel sticks her hand through Dipper, "Boop!"

Dipper scowled, "Mabel! What do you want with our uncle's mind anyway?"

Bill looks back at Dipper, "Oh, just the code to the old man's safe! Inside the shack is a maze of a thousand doors representing your uncle's memories. Behind one of them is a memory of him inputting the code! I just need to find it and Gideon will pay me handsomely."

"Not if we stop you!" Mabel shouts.

Bill laughed, "Hah, fat chance! I'm the master of the mind." Blue flame encircles him, "I even know what you're thinking right now!"

Will frowned, looking down, "Stop playing around..."

Mabel frowned, "That's impossible, no one can guess what I'm thinking!"

Bill makes Xyler and Craz appear.

Xyler smiled, "Whoa, where are we, bro?"

"We must be in heaven, 'cause I just saw an angel!" Craz points to Mabel.

Mabel hugs Craz's leg, "I'm never letting go of your leg!"

"You're out of your league, kids. Turn around now before you see something you might regret. Later, suckers!" He crashes through wall of mindscape Mystery Shack.

Dipper scowled, "We're goin' in! Mabel, can we leave those guys out here? Looking at them - hurts my eyes..."

"No! They can help us!" Mabel shouted.

Will looked down, "Sorry, Mabel..." He snaps his fingers, and Xyler and Craz disappear.

Soos runs into the shack in fear. Mabel yelps in surprise, before noticing a small blue triangle looking at them.

She frowns, "What do you want?"

"... Mabel..." Will sighs.

She backs away, "How... how do you know my name?"

"Mabel... please... I'm not going to hurt you..." Will holds up his hands, "Dipper?"

Dipper glares at him, "What?"

"This is why I believed you in the beginning," Will admitted.

Dipper frowned, "What are you talking about?"

"Look... you already know who I am... and I'll show you how," Will sighed, snapping his fingers, causing a flame to ignite in his hand.

Mabel gasped at the yellow flame, "Will?"

"... now do you trust me?" Will asked, "I might know him, but I would never hurt anyone. Not for any reason, unless I absolutely had to."

Dipper frowned, "Wait... you know him?"

"Yes..." Will looked down.

Dipper looked at Mabel, before looking back at Will, "Can you... give us a moment?"

"Sure."

Dipper leads Mabel away from Will, "Mabel... I'm not sure we can trust him."

"If we don't stop Gideon, we'll loose the shack. Besides, if he knows him, then maybe he knows how to beat him," Mabel smiled.

Dipper sighed, "That could be true, but still..."

"Dipper... if we don't, he could just leave us alone forever, and I don't want that. We have to trust him..." Mabel sighed.

Dipper frowned, "... but what if he's lying?"

"He already said that he didn't want to hurt anyone, unless he absolutely had to... besides, Grunkle Stan said he was benevolent, so... I say we trust him," Mabel smiled.

Dipper nodded, "Alright..."

The two walked back towards Will, "Okay... We'll trust you."

"Good. So... first things first." Will sighed, pulling one of his fingers up, and the two were in awe at the quickness that the hole in Dipper got filled, "Since we're in the mind, you can do anything you can imagine... powers or not... So, we have to stick together."

Mabel smiled, "Could we all have, like, a little thing to show each other that it's actually us?"

"Yes," Will sighed.

Dipper smiled, "So... what is that going to be?"

"It has to be different for each of us, that way he won't completely know," Mabel smiled.

Will smiled, "That would make enough sense."

"Okay..." Dipper makes a motion that's like a zipper over his mouth, "I'm not telling anything to anyone."

Mabel frowned, "We have to have some sort of code word too... something simple..."

"... like blue," Will sighed.

Dipper frowned, "Isn't that what he called you?"

"... yeah... He calls me Blue..." Will looked down.

Mabel nodded, "Alright. So... blue is the code word... my motion is going to be..." She grins, doing a small dance, that consisted of mostly just random dancing and a few ballet moves.

"I'm not going to remember that, Mabel," Dipper grumbled.

Will laughed, "I can, don't worry. Everything besides numbers is kind of easy for me..."

"Okay... so... what's yours?" Dipper asked.

Will grinned, snapping his fingers, causing a yellow flame to erupt on his index, before he put it by his lip, "The color is the most important part."

"Why?" The Twins asked.

Will sighed, "My flame is yellow, Gold's is a light blue."

"Gold is..." Dipper shook his head, "Yeah, I'm not going to question that..."

Everyone heads into the shack and awes.

Stan Bat, flying by Dipper walking down steps, "No refunds! No refunds! No refunds! No refunds! No refunds!"

Some of Stan's fears are shown.

The five enter Stan's memories.

Soos gasped, "Whoa, look! All of Stan's memories!"

Dipper grumbled, "Great. Sure there's plenty of memories of Stan bossing me around, can't wait to see more of that."

"Dipper..." Will frowns.

Mabel smiled, "Come on Dipper, we've gotta find the code before Bill does!"

"Let's get searching!"

They runs down hallway, panting.

Dipper opens a door, "Nope!" He closes the door.

Mabel smiled, "Whoa, it's Stan on a date! Yeesh." She closes the door.

Dipper discovers a door written 'Dipper Memories', "Look, guys! Memories about me!" He opens the door.

Soos frowned, "That doesn't seen like a good idea."

"I just wanna know what the old guy really thinks of me," Dipper sighed.

Mabel smiled, "We already know how Stan feels about us! He loves us! We're great."

"Yeah. Let's just keep moving."

Dipper walks a bit, but turns around and runs to the Dipper memories door and enters it, "Okay. Just a quick peek."

Will notices him by the door, and frowns, before following him.

Dipper walks by the doors. The sound Stan calling Dipper echoes. Dipper walks in front of one of them and opens the door. Inside is a memory of Stan making Dipper chop firewood.

"No buts! Now go and chop that firewood already!" Stan hits Dipper's head with a newspaper, making Will wince.

Dipper walks away to chop the firewood. Stan sits on the couch.

Soos sighed, "Dude, Stan, I've been meaning ask you. Why are you so hard on Dipper all the time?"

"Look, Soos, I'm gonna let you in on something. Wanna know what I really think?" He whispers to Soos.

Dipper leans to listen what Stan is talking, "The kid's a loser. He's weak! He's an utter embarrassment! I just wanna get rid of him."

"Keep listening," Will whispered from behind him.

Dipper jumped, looking back at him, before turning back to the memory and listening more.

"Heh, yeah. Those are all things people said about me when I was a boy," Stan laughed.

Dipper was confused, "Huh?"

"It was terrible. I was the biggest wimp on the playground!"

A door of Stan's memory opens behind Dipper. It shows Stan as a kid getting bullied by other kids and running with tears.

"So one summer, my pop signs up me for boxing lessons."

A door of Stan boxing opens. He is getting punched by his opponent.

"It was even worse than the school yard!"

Young Stan, "Left hook!" He punches his opponent.

Stan sighed, "Y'know, that time I thought my pop was trying to torture me."

A door of Stan at the theater opens.

"But wouldn't you know it? The old man was doin' me a favor all along!"

Man tries to steal Carla's bag, "Give me that bag!"

"Help! My purse! Help!" Carla shouted.

Young Stan, "Left hook!" He punches the man.

The people all around Stan cheers for him. Carla gives him a kiss.

"You see it? That why I'm hard on Dipper. To toughen him up. So when the world fights, he fights back."

"Do you think it's actually working?" Soos asked.

Stan points at Dipper.

Dipper, in the memory, chops the wood in a half, "I-I did it! Ha ha! Yes!"

"He's really comin' along! When push comes to shove, I'm actually proud of him. Just... don't ever tell him that. His head is big enough as it is," Stan smiled.

Soos laughed, "That's true."

Dipper grins and puts his hand on the memory. Will frowns, grabbing his hand, pulling him away from the door.

"Dipper... lets go. We... have to go..." Will looked down, biting into his lip.

Dipper looked at him, "Right... thanks for pushing me to listen to the entire thing."

"You're welcome."

Soos opens a door. Inside the door, Stan pushes buttons of the vending machine. The vending machine opens and a secret hallway appears.

Stan looked around, "If only people knew the truth, that hidden behind this vending machine, I secretly have a -" "-BORING!" Soos closes the door.

Mabel is in front of a door written "Top Secret" on top of it, "Alright guys, I have a good feeling about this door."

Mabel opens the door. Inside it has a memory of Stan in the bathroom, making her close the door faster than you can say, "SpegettiPastetti".

"Hah, we've been searching forever! What if the triangle guy finds the memory before we do?" Soos frowned.

Will glared at Soos, biting his lip. Soos looks over at him and gives him a small smile.

Will goes over towards Mabel and Dipper, making sure to keep some distance between him and "Soos".

Mabel frowned, "If we wanna find Stan's memory, we gotta think like Stan. He's always hiding stuff, right?"

"Yeah! Like how he hides his arrest warrants under that rug in the gift shop?" Soos asked.

Mabel smiled, "Soos, that's it! Look!" She walks to a rug and finds a door under it, before she opens the door.

Stan kisses the deed and puts it into the safe, "There ya go." He closes the safe door, "And now to input the code. 13, 44, and finally..."

Soos closes the door, "Dude! we found it!"

"Yeah! Um... um... Let's just destroy the door before Bill can find it!" Mabel smiled, finding a battle-ax.

Soos looks over at her, "Wait! Maybe I should do it! My big fat arms are great at destroying stuff!"

"Oh, okay," Mabel smiled.

Will glared at "Soos", before walking over to him, "You are never fooling me." He snaps his fingers, a knife appearing in his hand. The twins look at each other in surprise.

Soos, the real one, walks over to them, "Hey guys! I just saw a memory of Stan roller skating and wearing short-shorts! Didn't look... didn't look that bad! Hey, something weird is goin' on here."

Bill , in Soos' form, laughs; turns back to normal, "Boy, you kids sure are gullible! I knew you'd lead me straight to the code! It's funny how dumb you are."

Bill laughed, "The combination to Stan's safe. Boy, that was even easier then I thought!"

"Oh, yeah? Well, you're a-a stink face!" Mabel shouted.

"Later, suckers!" He flies away.

Mabel looks at everyone else, "Come on! We've gotta save Stan!"

"... Mabel..." Will fidgets with the knife in his hands.

Mabel looks back at him, "What?"

"... never mind..."

The door gets hit by a nyarf gun, "Ah! No no no! Wait, no!"

The door falls to the bottomless pit from one of Stan's memories.

"...and none more bottomless than the bottomless pit! Which you can see here is bottomless," Stan watched the door fall, "Whooh! Whatever that was, it's gone forever!"

The door closes. Behind Bill is Mabel who shot the door with a nyarf gun.

Mabel smiled, "Ha ha! Boom!"

"The Shack is safe!" Soos cheers.

Gideon scowled, "The deal's off!"

"Wa-wait! No! Wait!"

"I'm switchin' to plan B!"

The screen turns off and Bill's body cracks to pieces and falls off. Then Bill's body reappears as red.

"YOU! You can't even imagine what you just cost me! Do you have any idea what I'm like..., In a low, demonic voice, "WHEN I'M MAD?!"

Several characters pass by Bill's eye. Then a rock in the shape of Stan's head pops out from their feet and raises up. Bill's size starts increasing.

Soos sighs, "So I guess he gets really mad when he gets mad."

Bill, In a low, demonic voice, "EAT NIGHTMARES!"

Everyone screams.

"One nightmare, coming up!"

"Nightmare? Hope he doesn't mean that British dog man I'm always dreaming about..." The British dog man appears in front of Soos.

British dog man pokes Soos with his cane, "Ello, 'ello, 'ello! Who's crike for a stick in the pudding?"

Soos screams, "It's everything I've ever feared!"

The British dog man disappears, and Mabel turns around, staring at the light blue haired boy, biting his lip.

"Will...? Are you okay?" Mabel asked.

Will doesn't say a word, before he gets in front of them, "Leave them alone."

"Why should I?" He asked.

Will sighed, "If you want to hurt them, which you can't exactly do at the moment, then you'll have to go through me first."

"Fine!"

"You know, I've been impressed with you guys. You are more clever than you look. Especially the fat one."

Soos pokes Mabel; in a whisper, "He's talking about you!"

Will just glares at them, shaking his head.

"So I'm gonna let you kids off the hook. You might come in handy later. BUT KNOW THIS: A darkness approaches. A day will come in the future when everything you care about will change! Until then I'll be watching you! I'LL BE WATCHING YOU...," Bill disappears, his words echoing.

The gang wakes up in the living room, shouting in surprise.

Mabel smiled, "We did it!"

"What? Did what? What are you all doing here?" Stan asked, confused.

Dipper hugs Stan, "Grunkle Stan! You're okay!"

"What is this, a hug?" Stan asked.

Dipper smiled, "Nope! It's a choke hold," He chokes Stan.

Mabel and Soos laugh. Dipper stops choking Stan. Will just looks down.

Stan chuckles, "Not bad, kid. Not bad."

"I'm just glad Gideon didn't get into the safe. I really love this old shack," Mabel smiled.

"Group hug!" Soos pauses, "No? I never know the right time!"

The Shack starts to shake.

"Hey, do you guys feel...?" Dipper doesn't get to finish.

An explosion happens behind the sofa.

Gideon smiled, "Oh, I'm sorry, Pines family. Did I wake you?"

"But.. we defeated Bill!" Dipper shouted.

Gideon scowled, "Bill failed me! So I switched to plan B: dynamite!"

"No, he didn't! You're a fool, Gideon!" Will shouted at him.

Stan looked around, "What? Bill? Who? What are you guys talking about?"

"Spoiler alert, Stanford! I've got the deed!" Gideon shows the family the deed, lThe Mystery Shack belongs to me! So get out of my property!" He takes out a handheld transceiver, "Daddy? Bring it around the front."

Dipper frowned, "Don't worry, guys! It's just part of the dream! We're gonna wake up any second now! Right? Right?"

"Dipper... this isn't part of the dream..." Will mumbled.

Bud Gleeful drives a crane with a wrecking ball to the shack and smashes the Mystery Shack's sign.

Everyone, besides Will, screamed.

"Someone pinch me, dude..."

The broken sign falls in front of the gang.