Centuries ago, an elite band of thirty-seven, holy warriors called the Mighty would routinely slay thousands in a single battle. Today, the offspring of these heroes of old have all been hunted and killed.

Save one.

Augustine Caffrey is fifteen years old, seven feet tall and star of his high school wrestling team. Known as Og, the born fighter has never backed down from any human. Problem is the ungodly half-man/half-demon who has come to slaughter him today isn't really human. And when Og refuses the crossbreed's offer to join the wicked, his first battle against the demonic begins.

Og soon discovers that the father he has never met is responsible for the war that has come to his doorstep. A probe into his father's identity leads Og to a secret history of angels gone bad, a sacred law dating back to the Flood that clearly condemns the kid and blood ties that explain why both Heaven and Hell want Og dead.