Synopsis:

  At a gathering of Dorothy's first friends in Oz, the Wizard announces his latest invention, the ozoplane - a wonderful, magical craft that can zoom up onto the stratosphere.

  The Wizard, Dorothy, the Cowardly Lion and the Scarecrow get into one ozoplane (the Ozpril), and the Tin Woodman, Jellia Jamb (Ozma's maid-in-waiting) and the Soldier with the Green Whiskers (Baum called him 'Omby Amby' but curiously, Thompson calls him 'Wantowin Battles') in the other ozoplane (the Oztober). All of these characters were first introduced in The Wonderful Wizard of Oz except for Jellia Jamb, whom we first met in The Marvelous Land of Oz. Both groups have wonderful adventures and face many dangers, as the stratosphere over Oz is different from any other.

  Here the stratosphere boasts a country called Stratovania, ruled by the haughty King Strut (also known as Strutoovious the Seventh or Strut of the Strat). When the Tin Woodman and his plane of folks arrive here, the high-minded monarch takes a liking to Jellia Jamb and decides to make her his Starina.

  Meanwhile, the Wizard and his group soar onto the Red Top Mountains (rising high above the red Quadling Country) where Bustabo, King of the Kudgers (a not-too pleasant people who live on the mountain) has stolen the throne from lovely, red-haired fairy princess Azarine the Red.

  Note: In 1940, having contributed 19 titles to the Oz series (5 more than Baum, himself), Ruth Plumly Thompson retired as The Royal Historian of Oz.