Portions of The Hunger Games are available to read for free on Google Books. Here is a short summary.
Katniss, the protagonist, is a poor girl living in the coal-mining district of a post-apocalyptic country called Panem. Every year, the Capitol of Panem holds the Hunger Games, where children from each district are forced to fight to the death on public television, thus keeping the population under control. When Katniss's sister is picked, Katniss takes her place. A boy from her District, Peeta, is also picked, and he tells the audience that he is in love with Katniss, partly to gain favor and partly because it is true. After training and becoming popular in public opinion, Katniss tries to survive in the Games. She survives several attacks and is struck with the brutality of the Games when a very young girl is killed in front of her. She meets up with Peeta and plays along with the romance narrative, which is popular enough to spark a rule change; two may survive if they are from the same District. Katniss and Peeta survive to the end, and when the rule is reversed, she threatens to have both of them commit suicide rather than be forced to fight. The Capitol relents, and they return to their District; Peeta is disappointed that Katniss was only pretending to love him, while Katniss doesn't know if she can return to her old life after this experience.