Evening falls over the city of Cactus Flats, Arizona, and in it a young boy named Mike Powers rides his bike along the town's strip mall.
Barney opens the door to find a man and woman both dressed in cowboyish attire and very large gallon hats, making odd, raspy noises to each other in some unknown speech.
A family of four known as the Yeagher’s (Joe and Marilyn, and their children Charlie and Dena) are moving to town as a consequence of being in the witness protection program, being relocated from Brooklyn, New York and assuming new identities as the Vincenza’s.
Their caseworker, Marshall Dave, posing as an uncle informs them that they must refrain from outside contact and ensure to use their new names to avoid issues with Tony Marino, an imprisoned criminal who Joe “ratted” out.
Meanwhile, back at the pet shop, it is revealed that the new owners of the establishment, (Mr. and Mrs. Zimm) have transformed the backroom of the shop into a spaceship-esque room filled with advanced alien devices and an array of alien creatures, who possess a higher intelligence above earth animals as they respond to the Zimm’s commands and form an orderly line.
The Zimm's threaten the creatures and tell them they must transform into more earthly forms to avoid unwanted detection by the townsfolk, and then administer their special vitamins to them.
Mike visits Dena and tells her that these animals don’t exist in the encyclopedia and suggests the children all gather to try and find out why the Zimm's gave away all the pets for free.
The Zimm's activate a transport device as they brag amongst themselves about how they have duped the children since they did not give them any vitamins for the pets and how they will all have to return, and then be sold to pay their bills.
In the process, Mr. Zimm's hat is knocked off his head, revealing a bulbous forehead with a third eye, and gives them "the business," zapping each of the children with colored beams of light which paralyzes them.
As they proceed to transport the children, Joe interrupts and the Zimm's ignorantly leave the backroom open, allowing the creatures to escape.
Joe, still feeling the effects of the "Zimmer" beam, smashes his head through the glass of the store to give Dave and the others access since the door is locked.
Charlie pulls up in the family car, with a lipstick mark on his cheek, pursued by Gwen on a motorcycle demanding he come back.