Katherine A. Applegate

The Earth is being invaded, but no one knows about it. When Jake, Rachel, Tobias, Cassie, and Marco stumble upon a downed alien spaceship and its dying pilot, they're given an incredible power - they can transform into any animal they touch. With it, they become Animorphs....

Rachel is still reeling from the news that the Earth is secretly under attack by parasitic aliens known as the Yeerks. And that she and her friends are the planet's only defense....

When Tobias and his friends were given the power to morph, they were also given an important warning: Never stay in a morph for more than two hours. But Tobias broke the time limit, and now he's trapped in the body of a hawk - forever....

Elfangor-Sirinial-Shamtul is an Andalite war prince--the one who gave the Animorphs the power to morph. "The AndaliteChronicles" is the story of how this warrior-cadet ended up on planet Earth.

Ax is an Andalite, an alien, stranded on a strange planet he's sworn to defend, even though it's not his own. Since the Animorphs rescued him, he's fought at their side, and in that time they've come to consider Ax a friend. But deep inside, Ax knows he isn't their friend....

Eleven-year-old Willodeen adores creatures of all kinds, but her favourites are the most unlovable beasts in the land - strange beasts known as 'screechers'....

The Yeerks are finally starting to realize that the "Andalite bandits" are probably not aliens at all. That maybe they've been dealing with humans all along. And no one -- especially the newly appointed Visser One -- is happy about this revelation.

What would have happened if the Animorphs had never existed? If Jake and the others had taken the long way home from the mall that night, instead of cutting through the abandoned construction site? If they'd never met Elfangor. Never rescued Ax....

Jake seems to have grown up overnight–literally. When he went to asleep he was his usual kid-self, and when he woke up, about ten years had flown by! What's worse, the Yeerk invasion of Earth has succeeded.

Things were already really weird. Fighting aliens. Battling to have Earth. And still trying to be normal. Marco and the other Animorphs are almost used to it. But things are changing. The Yeerk invasion of Earth started out passively, secretly.

Jake has to attend a wedding out of town. No one has been designated to take over as leader of the Animorphs. But when Tobias tells the others that he's found the place where Visser Three currently feeds, there is a unanimous agreement on going after him.

Almost nothing could be as bad as finding out your mother is Visser One, the most powerful leader of the Yeerk invasion of Earth. But it happened to Marco. He knew there'd come a time when he'd have to face her again, knowing that the Yeerk in her brain has taken his mother away....

Jake's made an amazing discovery. There may be other people who know about the alien invasion of Earth. Others who know about the Yeerks. Jake finds a website devoted to revealing the existence of the Yeerks, but he and the other Animorphs suspect it might be too good to be true....

The blue box Elfangor used to create the Animorphs has been found by a kid named David. David has no idea what he has - or what it can do. But Marco does. And when he sees David with it, he knows the Animorphs have to get that box. At any cost....

David, the traitorous Animorph, is back. When the Animorphs decided to give another human being the power to morph, it was one of their biggest mistakes.

It all started with the dreams. But Cassie didn't pay much attention to them. She and her friends have been having nightmares ever since they acquired the power to morph....

We found out who Visser Four is. And he has found the Time Matrix, the machine Elfangor had hidden in the abandoned construction site. The same place we met him on a night none of us will ever forget. Especially me. Now Visser Four has the Matrix, and he plans to use it to become Visser One....

When Roscoe Riley finds a bottle of Super-Mega-Gonzo glue in the junk drawer at home, he can't resist tossing it in his backpack and taking it to school....

The Animorphs have one true ally in their battle against the Yeerks: the sentient androids known as the Chee. So when they discover that the Chee—including their friend Erek—are in trouble, they have no choice but to help.

The Animorphs have managed to contact the Andalite home world, but the battle is far from over. Visser Two has arrived on Earth, and he's not happy about the state of things.