Contains spoilers for this episode and earlier episodes.
Stan grows tired of Waddles getting underfoot and ties him outside the Shack. A huge flying creature snatches the pig, leaving Mabel frantic. Stan claims that it entered the house and that he fought bravely to protect Waddles, hiding his responsibility for the loss. Dipper organizes a rescue, although Soos's clumsiness makes him reluctant to bring his friend. McGucket helps lead the group into abandoned mines, where they discover prehistoric creatures preserved inside ancient tree sap. The summer heat has begun releasing them. Stan becomes excited about selling tickets to the discovery and accidentally reveals that he put Waddles outside.
Mabel refuses to speak to Stan, while Dipper loses patience when Soos ruins their trail through the caves. They find Waddles in the flying creature's nest, but the rescue separates Stan and the pig from the others. Faced with saving himself or protecting the pet Mabel loves, Stan fights the creature and brings Waddles back. Soos asks Dipper to trust him and leads the others past their attacker by using a blind spot directly in front of its eyes. Everyone escapes through a geyser, leaving the cavern behind. Mabel forgives Stan after seeing what he risked for her pig. Dipper apologizes to Soos, whose rescue has shown him why friendship requires more patience than he offered.