Underdog is an American television series which debuted to the NBC network and continued until 1973, for a streak of 124 episodes. Whenever such villains were victimizing love interest Sweet Polly Purebred like riffraff or Simon Bar Sinister Shoeshine Boy's epic alterego, underdog, appeared. Underdog nearly consistently speaks in rhyme, as in,"There is no need to fear, Underdog is here!" His voice was furnished by Wally Cox.