After the death of his mother, the evil mutant wizard Blackwolf discovers some long-lost military technologies. Full of ego and ambition, Blackwolf claims his mother's throne, assembles an army and sets out to brainwash and conquer Earth. Meanwhile, Blackwolf's gentle twin brother, the bearded and sage Avatar, calls upon his own magical abilities to foil Blackwolf's plans for world domination -- even if it means destroying his own flesh and blood.

In this story, Horton discovers there is a microscopic community of intelligent beings called the Who's living on a plant that only he can hear. Recognising the dangers they face, he resolves to keep them safe. However, the other animals around him think Horton has gone crazy thinking that there are such beings.