It’s easy to see Frank Morgan as Professor Marvel in the early, sepia portion of “The Wizard of Oz.” Indeed, one of the conceits of “The Wizard of Oz” is that the creatures that Dorothy meets in Oz have analogues back in Kansas. The Wicked Witch of the West is derived from the evil Myra Gulch (Margaret Hamilton), the angry neighbor who wants to murder Toto. The farmhands Zeke, Hunk, and Hickory are played by Burt Lahr, Ray Bolger, and Jack Haley, who not only would play the Cowardly Lion, the Scarecrow, and the Tin Woodman respectively, but who each give shout-outs to the qualities their analogues would have (Zeke shouts “Have a little courage!,” Hunk says “You’d think you didn’t have any brains at all!,” etc.).
This is also true of Professor Marvel, the itinerant con man and fortune teller that Dorothy meets immediately after running away. Professor Marvel, after sneaking a peek at a photograph in Dorothy’s running-away basket, convinces her to return home to her Aunt Em (Clara Blandick) who he says is falling ill from sadness because of Dorothy’s absence. She returns on her own, realizing that her home is important to her.
This will, of course, parallel the fact that Morgan also plays the Wizard of Oz himself at the film’s conclusion, and that the Wizard attempts to fly her home in his balloon. This is after he reveals himself to be a huckster who conned his way into the position of Oz’s local deity. He does, however, accidentally fly away without Dorothy, forcing Dorothy to return on her own and realize that her home is important to her.