Mirror mirror, hear my call… In the Fire world, seventeen-year-old Leah is the illegitimate daughter of one of the realm's most powerful lords. She's hot-blooded—able to communicate with the tempestuous volcano gods that either bless a civilization or destroy it. But then Leah discovers she's a Caller, gifted with the unique—and dangerous—ability to “call” her Otherselves in mirror worlds. And her father will do anything to use her powers for his own purposes. In the Water world, Holly nearly drowns when she sees—and interacts with—Leah, a mirror image of herself. She’s rescued by Ryan, a boy from school with a secret he’d die to protect. Little do they know, his Otherself is the son of a powerful volcano god at war in the Fire world…and he’s about to fall. As Leah and Holly's lives intersect, the Fire and Water worlds descend into darkness. The only way to protect the mirror worlds is to break every rule they've ever known. If they don’t, the evil seeping through the mirrors will destroy everything—and everyone—they love…

Behind the mirror lies your otherself... There is one True World, and then there are the four Mirror Worlds: Fire, Water, Air, and Stone. Audrey and Dorotea are “ otherselves”—twin copies of each other who live on different Mirror Worlds. On Air, Audrey has the ability to communicate with wind spirits. As war looms, she’s torn between loyalty to her country and her feelings for a roguish phantom who may be a dangerous spy. Blackouts and earthquakes threaten the few remaining humans on Stone, who have been forced to live underground. To save her injured sister, Dorotea breaks taboo and releases an imprisoned gargoyle. Brooding, sensitive Jasper makes her wonder if gargoyles are truly traitors, as she’s always been told. Unbeknownst to them, they both face the same enemy—an evil sorceress bent on shattering all the Mirror Worlds.

What she can’t remember could ruin her life. The Mirror Worlds are but dull reflections of the True World, where magic and technology blend together… On the True World, Belinda Loring has known from childhood that she must Bond with the son of another noble First Family. Uniting the families ensures hers will hold onto its powerful position, and so she’s always pushed down the tender feelings she has for her best friend—gorgeous, steadfast Demian, who isn’t noble. But when the ceremonial magic goes disastrously wrong, Belinda becomes a national disgrace. Scorned as Broken, she turns to Demian for help getting revenge on the man who ruined her: the radical Malachi. But the seeds of Malachi’s murderous plans lie buried in Belinda’s past, in the dark days of her kidnapping—a period of which she has no memory. And Demian may hold the key to recovering all that she’s lost—and saving the worlds.