It was fun to watch the characters unravel the clues and young readers will enjoy figuring out the cryptological messages left by the thief for what turns out to be a believable reason.
Although this book is second in a series and some references to earlier events are not explained in detail, it stands alone comfortably.
However there is one problem with it. The publishing house, North Star Press, is in need of a good copy editor. The dozens of errors, such as misused homonyms, were annoying and pulled me out of the story. But, unlike a college English major like me, most kids who read the book probably won't even notice the mistakes and will simply enjoy the mystery.