Idaville's secret weapon against lawbreakers, ten-year-old Leroy "Encyclopedia" Brown, helps the police force solve ten new cases, the solutions to which are found in the back of the book.
Encyclopedia Brown, the super sleuth in sneakers, solves ten new mysteries, including "The Case of the Slippery Salamander," "The Case of the Banana Burglar," and "The Case of the Dead Cockroach."
The solutions to 10 mysteries solved by Leroy "Encyclopedia" Brown are given in a separate section challenging the reader to match wits with the 10-year-old mastermind of Idaville's war on crime.