Sophie Harper has a secret. A peculiar one. By the time she gets to the Academy for Peculiars, she's already killed a man. From there, she learns that the superhuman strength she was born with and abandoned because of means she's a peculiar - a human with abnormal DNA - yet that same strength alienates her from her peculiar peers because of its rarity. As she settles into her new home, she makes friends with her dorm mates, stresses out about catching up with schoolwork, and starts dating one of the most popular guys at the academy. Normalcy is what Sophie wants more than anything, but she can't change the fact that she's different, even among peculiars. She starts falling for her infuriating trainer, a rugged shifter named Will, despite the fact that it's forbidden. When she finds out there's only one other man with her physical strength, she yearns to learn more about him - yet he's someone everyone refuses to discuss. She starts to realize that being a peculiar means more than just being strong, and that just she shares her ability with her mysterious counterpart, it doesn't mean he isn't a threat.

Those that aren't lost can't be found. After the whole ordeal at the underground Catalina nightclub, Sophie is ready to forget about everything and enjoy the holidays with Will in Washington. As the weather cools down, things between them heat up. But Sophie is still with Jason, and she can't easily forget that. On top of that, Sophie receives a letter from her parents wanting to meet and asking for her forgiveness. When Jane Cabot, her best friend, is mortally wounded by an unknown assailant, Sophie must question everyone and everything around her in order to bring her best friend to justice. Things don't add up, however, and despite Jane being attacked, Sophie is the true target. When she gets taken by a familiar face, pieces of a puzzle start to fall into place, and she's not sure she wants to be found.

Danger lurks in the most familiar places. When General Arbuckle reveals the peculiar existence to the world, the Academy of Peculiars is forced to close as a way to protect the faculty and students. Sophie Harper is more focused on the fact that her best friend, Jane, may actually be alive than Arbuckle and the United States military. Daryl's older and mental brother, Marvin, is quick to promise Jane's safe return after brokering a deal with Daryl and Ethan, the academy's dean. But something doesn't sit well with Sophie about Marvin, and if Jane wasn't involved, she's certain Daryl wouldn't have trusted his brother. On top of that, a familiar body winds up slaughtered at the academy gates. Now it's up to Sophie to figure out who could have done it and why, while dodging flying bullets and suspicious ex-boyfriends. Will wants nothing more to protect her; Sophie wants nothing more than find her friend - and herself. In the epic conclusion to the Stranger Series, Sophie will learn that just because someone is ambitious does not mean they're evil, those that she trusts the most have the power to betray her with relative ease, and the best relationship she can ever hope to have is the one with herself.

An undercover operation. Dark, deadly secrets. No one to trust. Brielle Morales still can't look at herself in the mirror. After the fallout from General Arbuckle's attack on the Academy of Peculiars and subsequent death, she is forced to come to terms with the fact that her choices nearly got her friends killed. She doesn't deserve redemption but when the AckPec dean offers it to her, she jumps at the chance. From this point forward, Brielle is a Seeker, an undercover spy at Arbuckle's own peculiar education facility, Zodiac Academy. Rumor has it that peculiars are being experimented on without their consent, and Brielle - along with Ellie Moyer - enrolls in the academy in order to discover the truth. As she starts to unravel the twisted secrets of Zodiac Academy, Brielle realizes that even her supposed allies are untrustworthy. Not even Ellie's gorgeous twin brother, Tom, is being completely truthful with her. Brielle has no choice then to trust in who she is, flaws and all, if she's ever going to figure out what's really going on at Zodiac Academy.