Don't Judge A Girl By Her Cover by Ally Carter

Cammie Morgan, a top student at an elite school that trains girls to be spies, is sent undercover to blend into a normal high school and investigate a mystery involving stolen secrets. As she struggles to act ordinary—juggling classes, new friendships, and a complicated romantic interest—her spy training collides with teenage life and she must use her skills to uncover who can be trusted before the threat escalates.

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