When the ancient Under Hill home of the Fae is infected with the Rot, they're left with an unpleasant choice: Die in one last, great stand, or escape to the Human world. A world they once knew, but where they no longer belong. A modern world, where Cold Iron surrounds and poisons magical beings.

The Fae Queen reluctantly chooses exile, and she and her people abandon their magical castles, ancient glens, timeless forests, and centuries of power and tradition. They come into a bleak land bereft of magic and wonder, and begin to hunker down in the Human world's hidden places. The once-proud Fae resentfully begin a life of poverty, anonymity, and fear.

But one small group of Fae, accustomed to tinkering with the fabric of the universe, begin to develop an idea. An idea that will either give them a new world to live in, or wipe them completely from existence. An idea that could preserve them, or end them forever. An idea that requires the help of a young child's boundless imagination. An idea that will take them into the Never, a place forbidden and inimical to their kind.

It's a story that you think you know, but you've only ever heard a small part of it. A story that starts long before those three children flew in, and that has its epic conclusion long after they've gone.