Idaville's Pint sized slueth, Encyclopedia Brown, puts his mighty brain to test. During Idaville's 100th birthday celebration, the time casule left by its founder is discovered missing. It is up to Encyclopedia Brown to nap the thief. But it appears that the thief has other ideas and will not stop until Encyclopedia is a closed book! Can Encyclopedia keep out of danger?.
The solutions to ten mysteries solved by Leroy "Encyclopedia" Brown are given in a separate section challenging the reader to match wits with the ten-year-old mastermind of Idaville's war on crime.