It’s hard enough to be the new girl at school for Hailey Schick. Not only has she managed to piss off the popular kids, but Trevor, the boy she sort of likes, is a total social pariah. To top it off, nothing is what it seems at the University School. Eternally young sentinels from the parallel universe of Halcyon have infiltrated the school. The Halcyonians have found a “cure” for aging and can travel between dimensions. The rulers of Halcyon, are sending out sentinels to scout potential planets where their people could settle. Hailey and Trevor have a hard enough time dealing with high school drama, and now they’re supposed to save Earth.