I read this in the 4th grade and it changed the course of my life. It explains everything up to RSA with math that a middle schooler can follow, with exciting stories of cryptography and linguistics across history. Lots of cool spy stories!
I read it in high school and would agree, it got me really excited about cryptography and espionage throughout history, no undoubtedly helped me discover infosec and cryptography. I saw Simon Singh present an another launch later, very inspiring author.
