When Mabel discovers that her favorite boy band is actually a bunch of imprisoned clones, she sets them free, only to decide on keeping them for herself. Meanwhile, Dipper is convinced that Robbie plans to brainwash Wendy with a secret message hidden inside one of his songs.

Dipper, Mabel and Soos must travel through Grunkle Stan's mind to defeat a tricky dream demon summoned by Lil Gideon.