Mac can’t lose another friend. Even if he doesn’t want to be found. The ripple effect caused by Mac’s best friend Amy’s murder has driven Mac’s new love, Kyle, to leave Hemlock and disappear from her life forever. But Mac knows that Kyle plans to enroll in a rehabilitation camp, where he can live with other werewolves. She refuses to accept his decision, especially since the camps are rumored to be tortuous. So she sets out in search of Kyle with a barely sober Jason, and Amy’s all-seeing ghost, in tow. Clues lead Mac to find Kyle in a werewolf den in Colorado, but their reunion is cut short by a Tracker raid. Now Mac and Kyle are trapped inside the electric fences of Thornhill, a camp for young werewolves. As she devises an escape plan, Mac uncovers dangerous secrets buried within the walls of Thornhill, and realizes that the risk to the people she loves is greater than ever before.Thornhill is a return to a familiar world with a new danger to face. It's not necessarily always fast-paced, but Mac in constantly on her toes. She's walked into something complicated, something bigger than she expected, and she's off again trying to save everyone. But there are secrets in Thornhill, secrets that could and will do anything to keep from being exposed.Mac's involved in something bigger now, bigger than one girl's murder in a small town. This is something that could impact all werewolves, not just the few that she knows and cares about. This is something sinister, and, like in Hemlock, Mac's the girl pushing to get to the bottom of it. But as a normal human in a camp filled with werewolves, she's also in danger. She's weaker than them, she won't be able to stand up to any physical abuse the camp deals out to the others, but she isn't affected by some things the camp uses to control them, by bloodlust or by the camp's own devices.There's a constant underlying tone of danger and unease rippling throughout the book, which leads to a lot of Mac, Kyle, and Jason moving as quickly as their able to. There's a lot of problem solving for Mac to do, a lot of secrets for her to uncover, which is rather amusing since Mac's keeping a fair amount of secrets on her own. But that's how Mac is, she's selfless and devoted and helpful. She puts everyone's well-being above her own. In a book like this, it could get her hurt. Or worse.This book, like Hemlock, plays on a fear of the other, fear of those who look and act different. As those infected with the werewolf virus/disease, they're stronger, faster, and heal quicker than normal humans. It's, unfortunately, become ingrained in us to label people. Male, female, straight, gay, black, white, abled, disabled, cis, trans. We're still all people, still human beings. The werewolf aspect makes the difference between them and normal humans more obvious, exaggerates the difference with baser instincts, bloodlust, and sharp teeth and claws. With those, they're seen as 'inhuman,' as 'monsters,' and, for the good of those not infected and 'normal,' they need to be locked away. Which isn't good, it will only lead to conflict and potential bloodshed.As the second book in a trilogy, it has to keep Mac's overall story going, her ongoing issues with Amy's death, her complicated relationship with Kyle, and her complicated friendship with Jason. And it does, it introduces a new bigger problem with a more dangerous enemy, one who believed that what they were doing was right, than through pain and suffering and death a solution would be found. Considering how this ended, I'm curious as to how Mac's story will end. Not easily, of course, but I wonder how painful it will be for her.