General Mills breakfast cereal products are seen in the Unger household. The Underdog (1964) cartoon series was created by General Mills' ad agency to help promote their products.
References to the original cartoon series include:
- Secret identity as "humble and lovable Shoeshine Boy"
- love interest "Sweet Polly Purebred"
- speaking in rhyme
- causing significant property damage during rescues
- pill as source of super powers
- changing into costume in exploding phone booth
- explaining to crowd that he is "not plane, nor bird, nor even frog, just little old me: Underdog".
Another reference to the original cartoon: the name "Shoeshine" refers to Underdog's secret identity as the shoeshine boy.
A video game based off this movie was planned for the Wii, Xbox 360, and PlayStation 3, but was canceled due to the negative reception of this movie.
"Bar Sinister" is a heraldic term - a bar slanting to the left on a coat of arms signifying "bastard".