The Hunger Games series takes place in the dystopian post-apocalyptic nation of Panem, set in the future in the ruins of North America. The country consists of the wealthy Capitol, and twelve (actually thirteen) poorer districts that support the it. Every year, there is a televised death match known as The Hunger Games, created by the Capitol, to punish the districts when they attempted to revolt against the Capitol.
In the first book, The Hunger Games, Katniss Everdeen is chosen to go into Hunger Games after sacrificing herself for his younger sister, Prim, along with fellow tribute Peeta Mellark. They are trained by District 12's only living victor, Haymitch, and during an interview, Peeta confesses his love to Katniss. In the games, Katniss and Peeta work together to win the game, and defy the Capitol by having two victors. In the end, Katniss remains troubled over her feelings for Peeta and Gale.
In Catching Fire, Katniss learns that her defiance as inspired rebellion in the districts. President Snow threatens her if she doesn't stop the rebellion, but while she tours the districts, she actually fuels the rebellion. The president announces the 75th Hunger Games, a Quarter Quell, where surviving victors from each district have to go back to the arena. Katniss and Peeta are forced back into the games, and they team up with several other tributes. They manage to destroy the arena and escape with rebel forces from District 13. However, Peeta and their ally, Johanna, have been captured by the Capitol.
In Mockingjay, the last book of the series, Katniss returns home to find District 12 in ruins. She goes to the underground District 13, led by President Coin, and agrees to become the Mockingjay, the head of the rebellion. When Peeta is rescued from the Capitol, it is revealed that he has been hijacked to kill Katniss. Katniss and the Star Squad go on a mission to kill Snow, where many of the members die. Prim was killed by a Capitol hovership, but then Katniss finds out that the ship was controlled by the rebels. At Snow's execution, Katniss kills Coin instead of Snow. After that, Katniss and Peeta go back to District 12 and live together.