(This will make no sense unless you have seen "Manos: the Hands of Fate on MST3K. And even then...)
In this episode, named as a parody of Mystery Science Theater 3000, Dipper and Mabel find a strange remote, which Mabel claims is a "3D TV remote" which will turn on a 3D setting on the television. When they putthis batteries into the remote, it teleports them both into the universe of whatever is on TV at the moment on the channel turned on. What's on? "Manos: The Hands of Fate", the worst movie ever made. Dipper and Mabel try to avoid the "plot" as much as possible, but eventually, Torgo catches up to them. They escape, and then decide to split up to try and find a way out of the Manos universe. Mabel checks for a TV remote inside the house, but Torgo finds her and starts his "The MASter Liiiiikes yOU" rambling. Mabel hides in the closet. Later, Dipper checks around outside for a way out. He finds a place that has a bunch of poles with women in white robes tied to them. And tied to one of the poles is Mabel! Just then the Master wakes up and all of the ropes on the poles untie themselves, and the Master takes his really happy viscious dog down to the main plot at the house. The women all arrange themselves in a circle and talk about whether or not to include a family's female members in their cult. It doesn't take long for them to pair up and roll on the ground (presumably this is fighting, just watch the clip http://www.youtube.com/watch?v=tja9cTzgq5k 11:00-12:00) So then, the movie abruptly ends, and Dipper and Mabel are transported back home.