Burt rescues newcomer Tyler Reed from the government-protected Graboid known as El Blanco. It happens that Tyler is the new owner of Perfection's tourist business and he couldn't have come at a worse time. El Blanco is becoming more aggressive and the Perfection residents have to figure out why before they become the next meal.

Three people enter an abandoned silver mine and are attacked by a strange creature, which drains the water from their bodies. Rosalita thinks it's a ghost, but Burt knows it must be something else, especially when two government agents arrive in Perfection.

Burt finds and kills a Shrieker in the valley, only to learn it was a part of a government funded project to train Shriekers for rescue missions. But when a storm knocks out the equipment controlling them, the remaining Shriekers escape and multiply. Now to survive, the Perfection residents must make a stand at Burt's place.

A team of scientists find a deadly strange animal/plant hybrid growing in the valley. Burt, Tyler and Cletus work with them to figure out how to stop it before it spreads even further. Meanwhile, Perfection has to deal with an over-excited tourist named Larry.

Shriekers are spotted in Juniper, Arizona and Twitchell sends Burt and Tyler to handle the situation. However, the Fish and Wildlife Service are also in town and manage to kill five Shriekers. They also take one alive for study and when it gets a hold of some food, the Shriekers start to multiply again. Now Burt and Tyler have to stop them from massacring the entire town.