The Sins of the Fathers is a gritty mid-century family saga about a hardscrabble, multi-generational, multi-ethnic family set on the Western Slope of the Colorado Rockies. Glenn Steele is the son of an abusive Indian hating father. When his father launches into a drunken rage and attacks Glenn's younger brother with a knife, Glenn intervenes to save him. But his action triggers his father's banishment from the household by the authorities. Twelve-year-old Glenn must now fend for his mother and siblings as head-of-household and is burdened with guilt for his role in his father's banishment. Years later, Glenn's granddaughter discovers through DNA that she is part Indian. This sets in motion a road trip to the Mogollon Range in Arizona in an old pickup truck called McTavish. Glenn, his daughter Molly, and granddaughter Allie set off to learn the source of the unexpected genes and truths about his father that might set him free from a lifetime of guilt.