From the book:

Here is a story with a boy hero, and a boy of whom you have never before heard. There are girls in the story, too, including our old friend Dorothy, and some of the characters wander a good way from the Land of Oz before they all assemble in the Emerald City to take part in Ozma's banquet. Indeed, I think you will find this story quite different from the other histories of Oz, but I hope you will not like it the less on that account.