A 13-year-old brainiac invents an ingenious listening device, which he uses to bring a crooked city official and his pals to justice
as Mayor Massey
as Charles Blackburn
as Fred Benson
as Alvin Fernald
as Shoie
as Daphne 'Daffy' Fernald
as Doyle Reager
as Miss Pinkney
as Mr. Fernald
as Mrs. Fernald
as Mrs. Hundley
as Herb Evans
as Mrs. Blake
as Ed Haskins
as Mr. Hodges
as Police Chief
as Sam Preston
as Sgt. O'Halloran
as Shorty
as Commissioner
as Greta
as City Engineer
as Worm
as Reporter
as Mrs. Barkley
