For as long as seventeen-year-old apothecary Rose Allgood can remember, the towering stone Wall surrounding Noah's Valley has protected her people. No one leaves. No one fights. And no one questions why.

But their paradise has been hiding its thorns. When Rose's mother becomes the Valley's first murder victim and her twin brother is swiftly condemned, she alone is searching for the real killer. Determined to find the truth, she follows a trail of hidden messages, forbidden knowledge, and whispers of a past no one dares to remember.

The deeper she digs, the more certain Rose becomes that her mother's death was no accident. That the Wall isn't just keeping something out. It's keeping something in.