My latest Oz adventure was The Lost Princess of Oz (1917). After books that hardly took place in Oz at all, and ones that recycled characters from other Baum books, The Lost Princess of Oz is a return to form for the Oz series, and ended up being one of my favorites.
In this book, Dorothy wakes up to discover that Ozma is missing. And not only Ozma, but also her magic picture that can show you what anyone in the world is doing at any time, the Wizard's magic equipment, and Glinda's potions as well as her magic record book that writes down anything important happening anywhere. Since one of these items is usually the deus ex machina that saves the day in the Oz books, I was immediately excited about an Oz story where these crutches were taken away.
The book reads like a mystery where groups of our favorite characters spread out to the four corners of Oz in search of their princess. We are latched onto the group containing Dorothy, Toto, the Wizard, the Patchwork Girl, the sawhorse, Betsy Bobbin, Trot, the Woozy, Hank the mule and the Cowardly Lion (whew). And to top it all off, this group is later joined by Button Bright, the little boy who is always getting lost and then found again.
Various adventures ensue as the group makes its way into the unexplored regions of the Winkie country (including an awesome spinning mountain range). At the same time that the group is heading out in search of Ozma, a woman from the isolated land of the Yips named Cayke the Cookie Cook realizes that her magic jewel-encrusted dishpan has been stolen! She needs it to make her awesome cookies so she and a giant frogman (who used to be a regular frog but grew to a large size in a magic pond and now wears fancy clothes and acts very wise) leave their sheltered country in search of it. The parties naturally join, after also picking up a Lavender Bear (the king of the teddy bear country) and his tiny wind up pink bear that can answer any question. This is a lot to keep track of.
Rest assured that mysteries are solved and things are returned to normal. It all boils down to an overly ambitious shoemaker (and really, doesn't everything?). This reads as a very nice adventure story, and even though a few too many characters are crammed in there, the book makes an excellent addition to the Oz universe.
[And, as always, you can read the whole thing here. Don't you love the public domain?]