The Animorphs are Jake, the leader (who dreams of someday being a Cable Guy); Cassie, an animal expert; David, the one who joined the team by finding the Blue Box; Marco, a young kid who loves jokes; Rachel, Jakes cousin; Tobias, a Red Tailed Hawk*, and the Andalite Aximili Esgarrouth Isthill.
The Animorphs stroy begins like this: Five young teens were walking out of the mall on a Sunday afternoon. They walk through a construction site and see a spaceship landing. The door to the ship open and an Andalite emerges. An Andalite is a deerlike being who can only communicate telepathically because they have no mouth. Anyway, the Andalite's name is Elfangor. He tells Jake and the rest of His friends about the Yeerk invasion. He tells them how the Yeerks are trying to take over peoples minds and the only way to fight them is to give them the power to change into any animal they touch. He tells Jake to go into His Spaceship and get a Blue Box. Using the Box, Elfangor gives the teens the power. However, they could only stay in an animal state for 2 hours or they would be stuck as that animal unless someone is able to break the spell. After they got there powers, another ship landed. Out came another Andalite, His name was Visser Three. Visser Three was really a Yeerk posessing an andalite body. He told Elfangor He would eventually conquer Earth, but elfangor said His plans would fail. With that, Visser Three changed into a viscous alien, took Elfangor, put Him in His mouth, and He swallowed Him up. The teens were terrified to look at it happening!
Now the teens fight the Yeerks. The Yeerks have ways of luring people into being posessed. They used people's bodies to create an organization called The Sharing. This seems like a family get together, but really it's a way for Yeerks to get into peoples bodies, they take unsuspecting people down into a secret cavern called a Yeerk Pool. The forcibly dip a persons head into a sludgy pool and a Yeerk crawls in His head. The Yeerks themselves have a weakness, though. They need Ultraviolet rays from the Sun to stay alive, so every three days, they and there host body return to the Yeerk Pool. The host body is locked up in a dungeon while the Yeerk soaks up on the Sun's Ultraviolet Rays. The Yeerks returns to the hoat and that person's slavery to the yeerk continues.
Soon after they have there powers, they meet an Andalite named Aximili Esgarrouth Isthal. He can change too. And He tell them He is Elfangors brother. He seeks to defeat Visser Three and avenge Elfangor.
Later in the series, a boy named David discovers the blue box, He tried to sell it on the internet, but He is stopped by the Animorphs. Visser Three comes after the box, but the Animorphs manage to hang onto it. David, who wake up with the Animorphs, is told about the invasion and they decided to let Him join the team. At first, He tries to destroy the other, but the team warns Him about the dangers of being an Animorph. After the battle, though David gets stuck being a rat. We had to take Him to the Witches Council to make Him human again. After He returns to being Human, He apologizes to the other for giving them such a hard time. Now David is back on the team and He knows what side His is on.
So if You want to know more about the Animorphs, just read the books. And You can go to the official site: www.animorphs.com
*Tobias used to be human, but He got stuck being a Red Tailed Hawk because He remained in the morph for more then 2 hours. Animorphs must return to Human state before the 2 hours is up or be stuck being that animal until the Witches Council can remove the spell. A creature stuck in a morph is called a Nothlit.