A young delinquent defies his sister to join a tough street gang.

In order to put an end to Joy Ryan's effort to organize her neighborhood against the corruption of City Hall, Alfred Martino, a crooked land speculator, frames Joy's brother Gabe, a reform school graduate, for arson. Gabe's pals, the members of the Termite Club, then decide to go to work on the side of law and order to bring the real arsonists to justice. After studying night and day to win the position of honorary mayor during Boy's Week activities, club member Billy Shafter appoints his pals as police commissioner and fire chief. Working with Pat Remson of the district attorney's office, the boys uncover evidence that proves that the fire commissioner is involved in an arson racket to collect insurance payments. After Martino's thugs, Kroner and Shuffle, are caught at the scene of a fire and released before they can be questioned, the boys enforce some antiquated laws and, with the support of the police department, pillory the thugs and take their case to the people. Upon learning that their boss is planning to flee the country, Kroner and Shuffle confess everything, and with Martino's arrest, the city is swept clean of corruption, Gabe is exonerated and Pat and Joy are free to marry.