The twelve districts of Panem are run by the Capitol, and as a punishment for a rebellion long ago are made to select a boy and a girl who will be tributes who will fight to the death in the Hunger Games, which are held every year. Primrose Everdeen is chosen to be the tribute for District Twelve, but her older sister, Katniss, decides to take her place. She is taken to the Capitol along with the boy tribute from District Twelve, Peeta Mellark. They are joined by their mentor Haymitch Abernathy, the only Hunger Games winner hailing from District Twelve. Haymitch gives Katniss and Peeta advice, telling them to get sponsors so that they can be provided with gifts that they will need during the Games.
District Twelve's tributes begin their training alongside the tributes from the other districts, but Katniss realizes as she watches them that they have been training their whole lives to participate in the Games. Peeta is interviewed on television by Caesar Flickerman, and declares that he loves Katniss, but she thinks this is an attempt on his part to get extra sponsors. Later she learns that he is telling the truth and that he has genuine feelings for her.
The Games begin; Katniss promptly ignores everything Haymitch has told her and gets supplies from the starting point, in doing so only narrowly escaping death. Twelve of the starting twenty-four tributes are killed in the chaos of the starting line. Katniss strategizes that her best chance is to stay away from the other competitors but the Head Gamemaker, Seneca Crane, does not like this idea and starts a fire in the forest to make her head back towards them. When she reaches the others she finds that Peeta has formed an alliance with the Careers - Marvel, Glimmer, Cato, and Clove - and so she quickly shins up a tree, but they spot her, and Peeta advises them to wait her out. She sees District Eleven's tribute, Rue, also hiding in a tree. Rue shows her a nest of tracker jackers, a genetically modified type of venomous wasp. Katniss takes her knife and saws through the branch that the nest hangs from, and it falls directly onto the Careers. Glimmer is stung to death but the others run to a lake and jump into safety. Katniss is stung a little herself and imagines that she sees Peeta telling her to away.
Rue and Katniss become friends and decide to work together to defeat the others. Katniss destroys the supplies that the Careers have stockpiled and Rue draws their attention away from her while she does. Rue gets caught up in a net trap, and Katniss frees her, but it is to no avail as Marvel impales her with a spear that he was intending to hit Katniss with. Katniss shoots him dead with an arrow. She stays with Rue as she dies and scatters flowers on the body.
After Rue's death, Katniss makes a three-finger salute to the television cameras which incites a riot in District Eleven, prompting a stern warning to Crane by President Coriolanus Snow. Haymitch manages to convince Crane to allow two winners if they are from the same district. Katniss hears this change announced and searches for Peeta, but finds that he is wounded. Another announcement tells competitors that what they each need the most will be provided the next morning at the Cornucopia. Katniss falls for this. She is ambushed by Clove who then gloats about Rue's death. Thresh, the male tribute from Rue's district, District Eleven, breaks Clove's skull in anger. He does not harm Katniss because he knows that Rue would not want him to. Katniss grabs the medicine that Peeta needs, and is heals him.
Katniss hears the cannon fire that signifies death as she is out looking for food, so she races back to where she has left Peeta. He has erroneously collected deadly nightlock berries, and District Six's female tribute ate handfuls of them because she assumed he was collecting them to eat, and that they were safe.
Crane lets out genetically modified creatures to chase down the competitors. Thresh is killed, and Katniss, Peeta, and Cato are chased up onto the roof of the Cornucopia. They are the last three standing and must fight. Cato gets Peeta in a headlock and uses him as a shield so that Katniss cannot shoot her. However, she shoots him in the hand with an arrow, so that Peeta can throw him from the roof. He is torn limb from limb by the creatures baying at the competitors, so Katniss shoots him dead so that he does not have to suffer.
Believing they are the duel winners, the two hear that the new rule change has been suddenly revoked. Peeta tells Katniss to shoot him but she refuses, saying that they should both eat the nightlock berries. As they are about to do so, Crane declares that they are co-victors. As they celebrate, Haymitch warns Katniss that she has made a lot of enemies with her defiance and that she should be careful in the future.
