Dorothy Costume Ideas & Inspiration. Follow the yellow brick road to the party this Halloween when you dress up in one of our lovely Dorothy Costumes! If you have been a huge fan of the Wizard of Oz since it first came out, then you are absolutely going to love our authentic Dorothy costumes. When Dorothy 5/5. Dorothy: All Halloween Costumes. Target / Holiday Shop / Halloween / Dorothy: Adult The Wizard of Oz Dorothy Halloween Costume Plus Size () Rubie's. 1 out of 5 stars with 2 reviews. 2. $ Adult Dorothy Low Heel Slipper Halloween Costume .