Plot: Underdog is an American animated television series that debuted October 3, 1964, on the NBC network under the primary sponsorship of General Mills, and continued in syndication until 1973, for a run of 124 episodes. Underdog, Shoeshine Boy's heroic alter-ego, appeared whenever love interest Sweet Polly Purebred was being victimized by such villains as Simon Bar Sinister or Riff Raff