"Johnny Tremain" is a novel set in Revolutionary-era Boston about a 14-year-old silversmith apprentice, Johnny Tremain, who has a quick temper. His arrogance causes another apprentice in the household to play a practical joke that disfigures Johnny, forcing him into finding a new trade. His friend Rab Lorne leads him to a new trade delivering newspapers and to a new life as a politically active Whig.
During this coming-of-age story, Johnny Tremain moves from being a self-centered, egotistic boy to being a noble-minded and noble-hearted young man. His evolution comes from a fall from grace, when his talent of silversmithing is taken from him through a burn, and his link to a prominent family, the Lytes, is denied. His growth stems from the humility Rab Lorne, a printing apprentice Johnny meets by chance during his search for a new trade, provides with gentle guidance and assistance. The Lornes produce a Whig newspaper, which is how Johnny Tremain becomes involved with the party, ultimately becoming a spy as the Revolutionary War approaches.
The Lytes eventually recognize Johnny's claim to the family. Johnny falls for Cilia, the daughter of his original master and a servant in the Lytes' home. Rab is killed in the early days of the war, and Johnny learns that the injury that took smithing from him can be at least somewhat repaired.