As is the case in many pieces of literature, there are several possible themes or main ideas in Catching Fire, the second book in the Hunger Games trilogy by Suzanne Collins. Government control, survival, and the responsibility that comes with power are three themes that can be identified in the book.
Catching Fire is a dystopian novel, which means that government control plays a very important role in the novel's plot and is an important topic; in fact, the Hunger Games only take place because of Panem's government's belief that it must control its citizens. The existence of District 13 is obscured from those who live in Panem in order for the government to maintain control in the way it prefers. Nearly every element of Katniss's life is subject to some intrusion by the government, from the food she eats to her loved ones' well-being.
Katniss, Peeta, and the other tributes must overcome seemingly insurmountable odds to survive not only in the arena, but also in their everyday lives. The need to survive dictates the decisions Katniss makes and forces her to sacrifice many things that she holds dear, especially her relationship with Gale.
The idea of responsibility is critical to the development of Catching Fire. There is a question as to whether Katniss is responsible for the citizens of District 12 (and the others), since President Snow forced her to play the role she embodies in public. Also, is Peeta responsible for Katniss because she saved his life? Haymitch's responsibility to protect Katniss and Peeta, District 13's responsibility to help the innocent citizens of Panem, and Katniss's responsiblity for Prim and her mother are also matters related to the main idea of responsibility.