Since the beginning of time, a secret war for control has been fought between two worthy adversaries: cats and dogs. Unbeknownst to humans, this struggle has been held in check by an uneasy truce. But that period of peace is about to come to an end. A power-hungry Persian cat, Mr. Tinkles, has broken from the fray to lead a massive feline movement against man's best friend. The crack canine agents, who have been protecting the human race, are in trouble. One of their top field dogs has been put out of commission and they have never been forced to employ the use of a rookie Beagle puppy named Lou. As the maniacal Mr. Tinkles and his army of well-trained soldier cats begin a mass mobilization, the fate of humankind rests on the paws of this young pup.