The group headed across the meadow to the structure, which they could see looked like some kind of large shed as they came closer.

There was another scream. This time they could hear it more clearly, and a familiar voice shouted,

"Please, stop!"

Stan's eyes went wide. "Stanford!"

The older man started running up the hill. The four young people behind him almost couldn't keep up.

When they came to the top of the slope, they saw no door on the side of the building they were on. Voices came through the thin wooden walls.

"Please, stop—I'm sorry that I've upset you—"

"Upset me? You used me as one of your little experiments!"

"But—I never performed any experiments on you! I only—"

"Shut up!" the other voice shouted, and there was another scream.

Dipper looked up at his great uncle, whose face had turned red.

"Stand back, kids !"

Before any of the young people had time to move, Stan pulled Stanford's large gun back, then rammed it into the wall. Mabel and Dipper just looked at each other. They'd only seen their great uncle behaving nearly this fierce once, when he tried to rescue Mabel's pet pig from pterodactyl. Now—

Bash! Crack !

Two of the boards broke, and Stan shoved his way through them, disregarding the splinters he might have received. After a second, Soos went in behind him. Wendy followed, then Dipper and Mabel.

On the other side of the large room, Dipper and Mabel saw their great-uncle Stanford bound to the beams on the wall by his wrists and ankles. His sweater had been pulled up over his head so that his stomach and chest were exposed. There were several long cuts on his body.

A young man stood in front of Stanford with a bicycle chain in his hand. He turned and smiled as Stan burst in.

"Well, well." He said. "You must be Stanley. "

Stan was seething. He aimed the gun at the man and his eyes narrowed. "Get-away-from my brother! "

The man stepped directly between Stan and Ford. "Oh, no-he hasn't paid for his crimes, yet. "

"He's done nothing!" Stan said through gritted teeth.

The shape shifter shook his head, and then looked over at Stan's young companions. "Ah. I remember you. I really should get back at you, too, for freezing me in that pod the way you did. "

Suddenly the man's body seemed to begin to melt. It became rounder, then longer, and a waxy white color. Dipper, Mabel, Wendy and Soos recognized that it was taking its true form.

Soon, what appeared to be large larvae appeared before them, with four legs in the back portion of its body. With one of the legs, which had a large claw at the end, it swung at Stan.

Stan ran to the side just as the claw came at him. "Missed, you freak!"

Stan looked down at the gun, then over at his brother. If I shoot this thing, I've got to be careful not to hit Stanford.

Mabel squeezed Dipper's hand. "What do we do? "

Dipper glanced over at his great uncle. "Come on. "

Hugging the wall, he started inching his way over to where Ford was bound. Taking his cue, Wendy, Mabel, and Soos followed.

The shape shifter ran at Stan, but Stan swung at it with the gun, hitting it in the head.

"What's the matter?" the shape shifter asked, turning its head back toward Stan. "Don't know how to use your brother's little toy? "

Stan looked at the switch on the side of the gun. There were three notches, one with an "S", one with a "M" and one with a "D". Currently the switch was set on "S". He looked over at his brother.

Aw, Sixer, what do these even mean?

Leaning back, he shot up at the creature's head.

"EEEEEEEEEEEEE!"

A chunk of the shape shifter's head was shot off, and small portions of it landed on Stan.

"Oh, disgusting." The man muttered, dodging the creature's claw again.