Conor hates life in Kansas, but she stays for one reason: to protect her sister from an unseen danger. That is, until the night her brooding classmate Jaime drags her into even greater peril.

Suddenly trapped in the mysterious realm of Asteria, Conor has no choice but to flee with him through dark forests and even darker tunnels. As they race to evade prowling fexes and sentinels, she learns of the mystical forces at play in every corner of this shattered world.

In the sea’s shadowy depths, Azra plunders ancient libraries in search of the lost magic that could save his doomed city. Atop floating towers, the imprisoned queen Skyye plots to escape before political intrigue brings everything crumbling down. Across the wintry meadows below, Evangeline fights to outwit an unlikely captor—all while plotting to retake her stolen throne and exact vengeance on her betrayers.

To survive, they each must confront the terror—and allure—of immortal powers beyond their reckoning. And whether by destiny or chance, one by one their paths converge with those of the “ordinary” teens who have stumbled into their dying realm.

Timeless myth collides with modernity in an epic fantasy that forces Conor to question everything she thought she knew about the world and her place in it. Ultimately, these unlikely heroes must decide what they truly value—and what they’re willing to sacrifice in the battle of their lives.