It’s been one year since Jonah Stone and his sister, Eliza, discovered that their mother is a nephilim, the product of a union between a human and a fallen angel, which makes them and their little brother, Jeremiah, quarterlings, or one-quarter angel. After embarking on an epic journey to rescue their mother and the other nephilim, who were kidnapped by fallen angels, the Stone kids have enjoyed a little peace and quiet.
But when Jonah and Eliza are attacked by fallen angels at school, they learn that quarterlings all over the world are being targeted, and separating them from their parents is the only way to keep them safe. The kids undergo special training to help them discover their own unique angelic gifts, which come in handy when they embark on a mission to find a mysterious prophet who they believe holds the key to Abaddon’s defeat in a massive battle between good and evil.