New York's charity balls mean boredom for Macey, daughter of a senator and a cosmetics heiress. She's been there, done that. At the latest one however, while she's staving off tedium by putting her security training to work, she spots a young man pickpocketing the Mayor. Intrigued, she follows him and learns that he's also wealthy. So why did he steal a cellphone?

DOUBLE CROSSED is in a series called Spies and Thieves about teenagers with special security training. The charity ball is crashed by gunmen who herd the bejeweled dancers together and force them to surrender their phones and portable wealth. Macey and her curious new acquaintance Hale can only watch - but Hale is in secret communication with someone outside, Kat. Managing to leave the group of hostages, the pair hurry down empty corridors and eavesdrop on a few of the terrorists who aim to bypass an apartment security system. Kat has been used in the thieving game many times in her fifteen years, and when Macey's security teacher makes contact with her they start to swap information. Mrs. Calloway's yellow diamond is the main target for the intruders, and they don't care that blowing the uncrackable safe open will rupture gas lines and endanger everyone.

The series posits a school called the Gallagher Academy for Exceptional Young Women in which genius girls are allowed to develop unusual talents and encouraged to work to good purpose. With lessons in advanced encryption and fourteen languages, the girls are pushed towards being spies. I did think that Macey could do with a lesson in staying unnoticed, as she is all too keen to show off both verbally and physically to an unknown young man the minute she meets him. But girls will be girls, and it is hard for teenagers not to demonstrate their abilities.

Certainly it's extremely positive to see young adult books in which using one's brain and learning self-defence are supported, not just field sporting ability or beauty enhancements. Ally Carter has clearly had a good time planning this book about a jewel heist, and put a lot of thought into her series. Try DOUBLE CROSSED on a bright young lady near you - and watch out!