Trivia: Here are some interesting tidbits about where some of the aspects of the movie came from, which is a compilation of the books following the first. Jack Pumpkinhead, the Powder of Life, the Gump, Mombi, Ozma (Tip) and the escape off the top of the roof all come from 'The Marvelous Land of Oz'. The multiple heads angle, the Gnome King's Nick-Nack game, the chicken coop, Billina, and Tik-Tok all come from 'Ozma of Oz'. The tunnel under the Deadly Desert that Mombi uses to get to the Gnome King seems to come from 'The Emerald City Of Oz'.
Trivia: Since the ruby slippers were created for the 1939 Wizard of Oz movie (the book used silver shoes instead), they are still protected by copyright. Disney had to pay MGM a huge sum of money for the rights to use them in Return to Oz, where they take the place of the magic belt in the books.
Trivia: Fairuza Balk (Dorothy) actually almost never wore either the Ruby Slippers or even her regular black shoes, except in certain shots where they were necessary. Any shot where her feet are not visible, she was usually barefoot. She found her black shoes intolerably uncomfortable, so the director allowed her to walk around without them most of the time and would only film her from the waist-up when possible. Additionally, the "rubies" on the Ruby Slippers kept falling off due to the hot stage-lights melting the adhesive material the "rubies" were attached to, so they only had her wear them in closeups or wideshots for short periods of time.
Trivia: Though the film is not intended to be seen as a direct-sequel to the classic 1939 version of "The Wizard of Oz", their sharing of several common elements (including the Ruby Slippers, which were created specifically for the 1939 film) caused Guinness to give "Return to Oz" the World Record for the sequel made the longest period of time after the original, at 46 years.
Trivia: The only film directed by Oscar-winning film and sound editor Walter Murch. During principal photography, some production troubles almost caused the film to be shut down. Murch's friend George Lucas (of "Star Wars" fame) evidently watched some of the footage Murch had already shot, and impressed by what he saw, convinced Disney to resume production.
Trivia: Along with "The Black Cauldron", "Return to Oz" was one of the first films to use Disney's then-new "Walt Disney Pictures" logo featuring a rainbow appearing over a white castle, set over a blue background. The logo and other close variants were used for most of Disney's releases until 2006, when they were officially retired.
Trivia: Dorothy's room at Dr. Wolly's electroshock therapy clinic is "31." (A reference to the day the holiday Halloween falls on.) "31" is also the number of the case Mombi's "original head" is located in when Dorothy later travels to Oz. This is in keeping with the tradition of aspects of Dorothy's "real world" being mirrored in the land of "Oz" - a concept introduced in the original 1939 Judy Garland film.
Trivia: Originally, there were many more scenes set in Kansas at the start of the film, including a scene of Dorothy and Aunt Em painting their faces and Belina getting into the kitchen of the farmhouse. They were removed for pacing reasons, so Dorothy would arrive in Oz earlier and the story could get moving.
Trivia: The scenes featuring Ozma at the end of the film had to be reshot months later after filming had wrapped. Originally, Ozma wore a long, regal golden-colored gown. During editing, the crew realised that due to the lighting and all the gold paint used on set, Ozma blended in too much with the background, like she was wearing camouflage. They then scrambled to reshoot the scene, with Ozma now wearing a white and green dress to help her stand out.
Trivia: Among others, Drew Barrymore and Alanis Morissette auditioned for and were considered for the part of Dorothy before Fairuza Balk was cast.
Trivia: Fairuza Balk did all of her own stunts in the film, which is something of a rarity for child actors.
Trivia: Christopher Lloyd and Tim Curry were both considered for the part of Dr. Worley/The Nome King.
Answer: She was in the human world so she was in disguise.