Sixth-grader Alton Barnes loves maps, and when his portfolio of secret maps is stolen, he begins getting notes with orders that he must obey to get the maps back but, with the help of a popular classmate, he just might succeed before his teacher, principal, or someone else learns he has been studying and mapping things about them.

As Benjamin Pratt and his friends Jill and Robert continue their efforts to save their school, they find themselves dodging two evil janitors, Lyman and Wally, but their team has also grown and now has a secret fund of millions of dollars.