I was trying to recall the name of this book just the other day! All the recent CA news had reminded me of it and I couldn't remember the name, but I remembered the cover.

In high school, we had to pick a math book to do a book report on. There were lots of people picking books like Flatland, but I ended up with "In Code". I actually thought it was a programming book because of the word "code" in the title. Turns out I was wrong, and I got exposed to learning cryptography as a high schooler! And since it was a book report, my reading culminated with me fumbling through explaining public key cryptography to my math class.