On Rhodenroode Island, a remote colony of the Homeland, there sits a Mission on the Hill, where boys are taken in and taught the ways of the faith. Darian is the only trainee of his race there, and he doesn't remember how he came to the Mission. All he remembers are brown hands and the belly of a ship. Life among the other boys and the cantankerous Brothers is not always easy, but Darian is determined to live up to the lofty calling the leaders of the Mission have laid out for him: that one day he will carry the Sacred Word to places it has yet to reach.

But when another trainee at the Mission disappears--the latest in a string of vanishings--Darian is determined to solve the mystery that begins to shake his faith in what he's always been taught. When he and his friend Micah sneak away from the Mission and head east to see what they can learn about the rebel sect supposedly responsible for the vanishings, they discover that the island holds far more secrets than they ever could have imagined--and somehow, they must save the other boys at the Mission from a danger that's even greater than they realized.