Dipper and Mabel discover that their seemingly cherubic new neighbor, Lil' Gideon, happens to be the town's adored psychic. But when Lil' Gideon guilts her into dating him, she and Dipper soon learn that his cuteness can fade all too quickly.

After being challenged to a video game battle by Robbie, Dipper is shocked when his favorite playable fighter, Rumble McSkirmish, comes to life to defend him. But Dipper soon loses control over Rumble McSkirmish and has to find a way to stop him.

Dipper is self-conscious that Mabel is taller than him and seeks a magic solution. Meanwhile Lil' Gideon takes advantage of Dipper's and Mabel's height discrepancy.

Dipper and Mabel go trick-or-treating in the summer and encounter a candy-loving monster who threatens to devour them if they don't bring him sweet things to eat.

The twins discover a hidden room inside the Mystery Shack and compete over who should have it.

The kids, along with Old Man McGucket's help, discover there is a secret society in Gravity Falls.