Dumbo, the fourth animated feature in the Walt Disney Animated Classics series, is based upon the storyline written by Helen Aberson and illustrated by Harold Pearl for the prototype of a novelty toy (Roll-a-Book).The main character is Jumbo Jr., a semi-anthropomorphic elephant who is cruelly nicknamed Dumbo.he circus director makes Dumbo the top of an elephant pyramid stunt, but Dumbo trips over his ears and misses his target, injuring the other elephants and bringing down the big top. Dumbo is made a clown as a result, and plays the main role in an act that involves him falling into a vat of pie filling.