What happens when mad scientist Dr. Simon Barsinister and a former police beagle Shoeshine are involved in a fiery lab accident? A dog with superpowers is born (soon to be dubbed Underdog) and Dr. Barsinister becomes a man obsessed with revenge and bent on genetically modifying the entire population of Capital City. An unwitting former policeman Dan and his son Jack adopt Shoeshine in hopes of improving their strained relationship and what follows is a typical scene of home destruction by a young dog multiplied exponentially by the incredible strength, speed, and newly developed language skills of one super dog.