Thirteen-year-old Riley Oh, an ungifted member of the Gom clan of healers, one of six gifted witch clans, embarks on a quest to save her sister Hattie's life when a spell to share Hattie's powers goes wrong. Riley and her best friend Emmett travel to an exiled clan to recover a fallen star and learn truths about the clans that have been withheld from them.

"Rick Riordan presents." Genealogical table on endpapers.