ELT The Super Dog's latest adventure continues as Walter Crum, who was last observed in a helicopter flying over Spring Valley after a foiled bank robbery, has been in seclusion. He and his cohort Sid formulate a devious plan to seek revenge upon the town of Spring Valley, and get richer at the same time, but what does he have in mind? His secret weapon....a crazed scientist named Cylus Devereaux.
Life in Spring Valley has been peaceful since the night of the Quadrasonian invasion, but Elt and the Valleydale pets fear that something terrible is about to happen. Their premonitions come true, for humans start disappearing, and stray dogs start appearing. The mystery is solved when the first transformation from human to canine is observed. These new hybrid canines have a leader, and he vows to make sure that his followers will never go hungry. What makes matters worse for Elt is that his human, Ralph Eltison, changes into a Labrador!
The super dog contacts Coladeus, who is engaged in a mission far away. The Trianthian recruits Sparky and other heroes, along with the Golden Retriever's human, Amy Pendergrass, to assist Elt and his friends. Elt, along with Sparky, the neighborhood pets, and Amy, must locate his former human, discover who is behind the canine transformations, confront the new species of hybrid canines, and transform these hybrids back to humans.