Like every good and sane person, Cassia Mooseroot spent her whole life avoiding the Ceoghast, a land of horrors where witches, hungry monsters, and soul-eating magic rule. Unlike those people, her ties to the Ceoghast run deeper than she could have known.

After her father casts her out and exiles her from her hometown, Cassia arrives in Midt, a remote village on the edge of the Ceoghast. Here, no one knows her secrets or history.

Among the devout townspeople committed to keeping the Ceoghast from encroaching on the Tenet Lands, Cassia begins to shape a new life, hopeful she's finally left the shadows of her past behind her. But when she joins a volunteer border patrol that takes her closer to the Ceoghast than she's ever been, she attracts a creature from the dark. Seeing this, her patrol partner calls her a witch. Accused of a crime punishable by immediate death, she flees into the Ceoghast.

In more danger than she's ever imagined, Cassia accepts help from a mysterious stranger, a ceogot who takes her to a place of shelter. But everyone she meets in the Ceoghast has their own agenda, and staying in the cursed lands puts more than just her life at risk - her very soul is on the line. Desperate to find her way home and stop the execution that awaits her there, she devises a daring plan to prove her devotion to Midt. But as her plan comes to fruition, Cassia begins to question: In which world does she truly belong?