A space craft crashes on Mr. Leopolds farm, and his four foster children get involved with helping the alien inside it. The cargo is "Endlings", end of the line animals and creatures who have been temporarily miniaturized for transport.
As the ship crashed some of the Endlings became full size creatures. The alien shows them how to shrink them back into their ball cages. Mr. Leopold is unaware of all this.
The alien wakes up in the bathtub, and is startled by Gabby. The elephant has a tracking device and the tracker is on her way to the farm. Also on the way are the police and a gov't UFO tracker. All 3 for different reasons.
A giant worm tunnels under the farm and causes havoc. It attacks Gabby, Johnny and goes after Mr. Leopold in the field. The gov't UFO hunter and the Elephant tracker arrive at the farm just after the kids miniaturize it into the orb cage.
Abiona hits the alien with her car and claims Tuko the elephant. The alien hibernates itself to heal. A saber tooth cat is on the loose and menaces Tuko.
The kids capture four creatures, and race to get the cat before the police do. In the government lab, agent Hewes finds pieces of alien metal in the harvester she confiscated.
Tabby has to meet her mother who shows up late and tells her she can't live with her. Tabby finds a really cute endling that she wants to keep as a pet. She names him Trick.
Tabby tries to keep Tick hidden, but he is sick and another endling can help Tick. Tabby does not want to let him go. Agent Hewes sources the fourth piece of metal at the police station.
Mr. Leopold reminisces about his son. A creature who does not like the light is captured in the house. Agent Hewes finds the fourth piece of the the alien metal which makes up the orb cage.
Agent Hewes figures out how to use the four metal trap pieces. The alien recovers and the kids call him "Ling". The new endling is invisible but is not a threat. Tuko is kept warm in the barn.
The farm is infiltrated with hundreds of drones. The creature is caught in a giant bear trap that Agent Hewes had put all over the farm. The kids can't open the trap because the creature that is caught won't let them near her.
Mr. Leopold has a flashback about when Johnny first came to him. The kids fight the drones and win. Agent Hewes is caught out by the police and the kids use the endlings horn to make themselves invisible.
