Thirteen-year-old Aris Thorne has spent his life trying to find where he belongs. As a trans boy in a small town, he’s used to being the odd one out—but he never expected to be the key to a world hidden in the shadows of our own.

When Aris accidentally "folds" reality to escape a confrontation, he is pulled into Aetheria, a realm of impossible architecture and ancient magic. At the prestigious Meridian Academy, Aris learns he is a Seam-Walker, a rare individual capable of treading the very lines that hold existence together. But while his classmates master the art of Tethering and Echoing, Aris discovers a terrifying truth: the seams are fraying.

A shadowy group known as the Unravelers is determined to tear down the barrier between worlds, and they believe Aris is the only one who can help them—or the only one standing in their way. With the help of a loyal group of outcasts, Aris must embrace his true self and master a power he barely understands before the world he’s finally started to call home disappears forever.