Picking up right after the events of the episode “Dipper and Mabel vs. the Future", the apocalypse begins, and Dipper and Wendy head out east in attempts of rescuing Mabel. Dipper, Wendy, and Soos find themselves in a fake reality fueled by Mabel's imagination, and need to convince her to leave the bubble before they get tricked in by its temptation. While Ford discovers Bill's true motives for his plans, Dipper, Mabel, Stan, and the rest of the resistance head out to stop Bill once and for all. When Bill traps the resistance members and threatens to kill Dipper and Mabel, Stan and Ford are forced to come up with a new plan to defeat him, but they will have to make the ultimate sacrifice.