Animorph World

Your Animorphs Central

Plot Summary

Thirteen-year olds Jake, Rachel, Cassie, Marco, and Tobias are walking home through an abandoned construction site, when an alien spacecraft lands nearby. The alien, an Andalite named Prince Elfangor, explains that the Earth is being invaded by another race of aliens, called the Yeerks, a slug-like parasitic species who infest humans through their ear canals and take complete control of the human's body. Elfangor says that more Andalites will not come to Earth until it is too late, and Earth will already be completely taken over - so to combat the Yeerks, he gives the humans morphing technology, the power to become another creature through absorbing their DNA. Elfangor warns them to never stay beyond two hours in a morph, or they will be trapped in that form forever. The Yeerks, led by Elfangor's arch-rival, Visser Three, arrive and eliminate all traces of Elfangor and his ship before proceeding to attempt to catch and kill the teenagers. The group escapes, shaken but more or less unhurt.

The next morning, Tobias visits Jake and informs him that the previous night was not just a dream: the Yeerks are real, and the teens really can morph. The five of them spend the morning at Cassie's barn, practicing morphing simple creatures like cats, dogs, and horses. A police officer arrives and informs the group that last night some teenagers were sighted setting off fireworks in the abandoned construction site, and the five of them realize that the police officer is a Controller. Later that day, Jake's brother Tom expresses a similar interest in the teenagers at the construction site, and Marco realizes that Tom is a Controller too, much to Jake's anger. Tom invites the group to a meeting of a local community club called The Sharing, which the teens quickly determine is a front for the Yeerks to acquire new hosts. They also discover their assistant principal, and leader of The Sharing, Mr. Chapman, is also a human-Controller. The next day Jake morphs a green anole lizard to spy on Chapman, and discovers that there is an entrance to the Yeerk Pool - a humongous, underground control center where the Yeerks can feed and recuperate - in their school.

The teenagers, newly christened as the 'Animorphs' (Animal Morphers) by Marco, head to The Gardens, a large zoo/amusement park, in order to acquire some new morphs. That evening they decide to infiltrate the Yeerk Pool in order to rescue Tom, but find that Cassie has been kidnapped by the police-Controller. With no time to plan a strategy, the four remaining Animorphs - including Tobias, who has already morphed into a red-tailed hawk - head into the Yeerk Pool, and while they manage to rescue Cassie, they find themselves outnumbered and outgunned by Visser Three and his Yeerks. The Animorphs escape, but not without loss - they fail to rescue Tom, and Tobias does not escape the Yeerk Pool and demorph in time, becoming a red-tailed hawk nothlit. Jake promises to keep fighting the Yeerks until the Andalites arrive. more...

Plot by: Wikipedia


  • A KASU [KA. Screw Up] Explained; so, what exactly IS the deal with Jake thought-speaking to Tobias while he's human, even though every other book says that's impossible? The answer's pretty basic: K.A. Applegate changed her mind about how thought-speaking works and forgot to change that part of the book. What a mistake — Animorphs Fans have been hounding her about it ever since!
  • In the original manuscript for this book, back before a proposed trilogy called "Changelings" became the Animorphs series Jake was named Matt and had a little brother named Joseph. Cassie didn't exist at all! Good thing for Rachel this was changed later on — she would have been totally outnumbered by the guys. Of course, knowing Rachel, she would have handled it just fine.

From the Anibase

  • The cover of The Invasion is the only one to feature six intermediate morphing 'stages'. The other books feature covers with only three stages.
  • The front cover quote is, "Some people never change. Some do..."
  • The inside front cover quote is, "Jake is changing..."

From Wikipedia



Morphs acquired

Morphs used


Golden Retriever ("Homer"), Green anole, Siberian Tiger

Golden Retriever ("Homer"), Green anole, Siberian Tiger


African elephant

African elephant


Cat ("Dude"), Red-tailed Hawk

Cat ("Dude"), Red-tailed Hawk





Gorilla ("Big Jim")

Gorilla ("Big Jim")

Visser Three


Antarean Bogg, 'Fire Creature'