Burt and the others struggle to find out what is wrong with El Blanco, who is behaving unusually aggressive. Meanwhile, a guy named Tyler Reed moves into town, taking over Desert Jack's Graboid Adventures.
After three people are sucked dry by a strange ghost-like creature in Perfection's abandoned silver mine, Rosalita thinks something paranormal is on the loose. When two government agents arrive in town, Burt realizes it is something else.
After Burt finds and kills a Shrieker in the valley, a government-funded science project with the goal of turning Shriekers into rescue animals is discovered. When the creatures escape, it's up to Burt and the others to prevent the multiplying packs from leaving the valley.
After a hang-glider is eaten, it is discovered that there is an Assblaster loose in the valley. It turns out it is the one Nancy sold two years ago, and she feels guilty. Meanwhile she, Jodi and Rosalita teach the students Burt's first survival class, with Burt busy with the Assblaster.
After two scientists are burned by acid, Burt and the others discover a bizarre animal/plant hybrid growing in the valley and hurry to destroy it before it spreads seeds.
Two Vegas mobsters arrive in Perfection, wanting to see El Blanco. After El Blanco eats one of them, swallowing an important key in the process, a hit is put on him, and Burt and the others must save him.
Protesters swarm Perfection, demanding the inhabitants to leave because their presence is supposedly harming El Blanco. El Blanco is behaving very erratically indeed. One of the protesters turns out to be Nancy's daughter, Mindy.
With Burt out of town, Tyler and a visiting scientist must save Perfection from swarms of flesh-eating insects which produce deafeningly loud sounds, courtesy of MixMaster.
Following several mysterious deaths at an artificial lagoon Melvin is making in Bixby, it is discovered that a giant brine shrimp, created by MixMaster, is on the loose.
