Title: Out of Sight, Out of Time.
Author: Ally Carter.
"With more than a million Gallagher Girls books sold, a legion of fans have fallen in love with the New York Times best-selling spy-girl series, and the fifth book delivers the most nerve-wracking, high-stakes adventure yet.
The last thing Cammie Morgan remembers is leaving the Gallagher Academy to protect her friends and family. But when Cammie wakes up in an alpine convent and discovers months have passed, her memory is a black hole. The only traces left of Cammie's summer vacation are the bruises on her body and dirt under her nails. All she wants is to go home.
But even the Gallagher Academy now holds more questions than answers as Cammie and her friends face their most difficult challenge yet. With only their training and a few clues to guide them, the girls go in search of answers on the other side of the world. But the Circle is hot on their trail and will stop at nothing to prevent Cammie from remembering what she did last summer."
Release Date: 3/13/2012