The novel, set in a fictional world called the Four Lands, consists of two intertwining plotlines. The first plotline follows the quest of protagonists Wil Ohmsford and Amberle Elessedil to create a new Ellcrys, a magical tree that serves to banish all Demons from the Four Lands. To do this, they must locate a specific place in the Four Lands called Safehold, where the process of creating a new Ellcrys can begin. The second plotline focuses on the efforts of the Elven army and their allies to slow a massive Demon invasion, made possible by the dying of the current Ellcrys, to give Wil and Amberle enough time to complete their quest.