Underdog’s mysterious origins begin in the wake of an accident in the high-tech lab of the maniacal scientist Dr. Simon Barsinister (Peter Dinklage). Suddenly, an ordinary, down-and-out young Beagle named Shoeshine finds himself with extraordinary powers, not to mention the unexpected ability to turn his bark into real speech.

Now, armed with a “fetching” superhero costume, this unlikely caped crusader and humbly self-described Underdog (voiced by Jason Lee) vows to protect the beleaguered citizens of Capitol City–especially one beautiful Spaniel named Polly Purebred (voiced by Amy Adams).

When a sinister plot by Barsinister and his overgrown henchman Cad (Patrick Warburton), threatens to destroy Capitol City, only Underdog can save the day.