T.B.S.D. starts out a bit slowly, with Tom's idyllic life at home, but picks up briskly when he arrives at Rugby. There he meets Harry East who becomes his best friend and ally. The school is overseen by Dr. Thomas Arnold, the headmaster. Arnold institutes many reforms at Rugby, which becomes an educational model for other schools in England. Although Arnold is physically in the novel only infrequently, his presence is always felt, and Hughes' deep respect for his former headmaster is clearly expressed through his main characters.
T.B.S.D. takes place at a time of transition, when Dr. Arnold is just beginning to introduce his reforms, and it highlights what Hughes clearly feels are the best and worst features of this system. The book can be roughly divided into two segments, each of which has a different focus. The first part deals mainly with the flaws in the system, which relies heavily on the influence of the oldest school boys- the sixth formers- over the younger ones. This influence, however, is only as good as the characters of the boys wielding it. When Tom arrives at school, a time of relatively moral leadership is drawing to a close, in the form of Old Brooke, the head boy of the sixth form, who is graduating. Physically tough and of a strong and steady character, he has held sway over the Schoolhouse. When he leaves, however, there is a lack of strong leadership in the sixth form, which is now populated by boys who are physically and/or morally weak. This allows a gang of fifth form bullies, once held in check by their fear of Old Brooke, to operate with impunity in the Schoolhouse, making the lives of the younger boys miserable.
As mentioned, the first part of the novel deals with this situation, or more specifically, with Tom and East's response to it. They decide to take a stand against Flashman and his minions, and their bravery in the face of intimidation and abuse inspires others to join them. For a while, the Schoolhouse is a clandestine war zone as the lower form boys fight for their rights. What follows is an interesting read, detailing Tom and East's trials and tribulations, and ultimately their triumph over Flashman.