A young father takes his nine-year-old son, the family dog, and two of his son's friends backpacking in the mountains of Colorado only for all five of them to be struck by lightning.

The story of how a stray dog, Pluto, comes out of nowhere and impacts the Davis family, who are struggling in many ways. In just a short time, Pluto the Wonderdog manages to save a toddler, bring comfort and companionship to a hurting 9-year-old boy, help restore a marriage, and repair a broken father-son relationship. Pluto is not only a guard dog - he is a guardian angel.