Don’t Judge a Girl by Her Cover (Gallagher Girls, Bk. 3)

Here's the thing about covert operations: the really bad things always happen when you least expect them. The enemies don't give you a heads-up. And they never let you stop to put on comfortable shoes.

A spy-in-training, Cammie Morgan has a cover for every occasion. But what happens when she is forced to lose her cover to save her best friend, Macey? Cammie and her friends are determined to hunt down the group that threatens to tear their secret sisterhood apart. This time it's personal.