Reyna was born the night the sky turned red, and she's spent eighteen years wishing nobody ever found out. When a letter drags her to Ashfall Academy, a school built to train werewolves like her, she expects hazing, homesickness, and maybe a decent excuse to avoid her mother's silence about that night. What she doesn't expect is Kade, the alpha's son, warning her away from the east wing before she's even unpacked. Or the ground shaking the first night she's on campus. Or the rumor, whispered everywhere she goes, that she might be the reason an ancient evil sealed two hundred years ago is finally waking up. The truth is worse and stranger than the rumors. Reyna isn't the key to the curse. She's one of the locks, descended from the wardens who bound it in the first place, and something has been quietly working to break that binding from the inside for years. As she and Kade dig for answers neither the council nor his own father want found, a mark rises on both their skin, an ancient bond neither of them asked for and neither of them can quite bring themselves to regret. But someone close to them already knows more than they're saying. And the closer Reyna gets to the truth, the more it looks like the people meant to protect her have their own reasons for wanting the seal to fail. With the Hunger stirring beneath the academy and a council that sees her as a weapon before a person, Reyna has one choice left: trust the boy whose loyalty is already splitting him in two, or face what's coming alone. The moon doesn't forget who it marked. And neither does what's waiting under the floor.