After their victory in the 74th Hunger Games, Katniss and Peeta are sent on a 'victory tour' which is nothing but propaganda. Before they depart, President Snow himself visits Katniss for a threatening heart-to-heart. Snow is concerned that her actions in the games have inspired the districts to rebel, and it is now all on her to quell that rebellion by her behavior on the tour. Unfortunately for Snow, the first stop on their tour is District 11, the same district from which young Rue hailed, and to which Katniss sent a signal of solidarity upon Rue's death, a fate which she both witnessed and avenged.
After Katniss's speech, the crowd responds, starting with someone whistling the mockingjay riff, and everyone salutes Katniss. After the tour, they visit the capital and are again featured on Caesar Flickerman's show, where Peeta publically proposes to Katniss on air in an attempt to placate President Snow. But none of this prevents unrest in the districts which become more and more agitated, bordering on open rebellion.
Back in District 12, glad to be home and out of the limelight, Katniss takes time to herself in the woods around her home and encounters two people who are fleeing the authorities from District 8. They tell her that they believe that District 13 was not wiped out, and that people still live there - indeed, that it’s a clandestine sanctuary from the influence of the capital.
The next bombshell to drop is that the 75th Hunger games is a Quarter Quell - where something special happens: on this occasion, the contestants will not be selected by lottery, but will be the winners from all of the previous Hunger games. This means, of course, that both Katniss and Peeta will be competing for the second successive year! Katniss determines that she will do whatever it takes to insure that Peeta wins. Peeta determines that he will do whatever it takes to insure that Katniss wins.
The competition is set in a jungle environment this time, not in a forest, and it has been much more manipulated than it was previous year, and much more dangerous. As the games begins, Katniss and Peeta find themselves in an uneasy alliance with another victor, Finnick, and with his aging mentor, Mags. Mags dies, but their party is bolstered with the addition of Johanna, one of those competitors who was especially trained for the games by her district. They also link up with an old couple from District 3 Beetee and Wiress. The latter soon informs them that the arena is a circular, like a clock, and it's divided into sectors, each of which is triggered in succession once every hour, to provide obstacles and dangerous events for them to overcome.
These events soon rob them of Wiress, and Beetee reveals that the electrical discharges they've been experiencing can be harnessed and employed to destroy the encompassing fence, allowing them to escape the arena. Beetee fails to accomplish this, but Katniss manages it, although she's knocked out by the discharge, and she wakes to find herself being flown to freedom in District 13 along with Finnick and Abernathy. Peeta and Johanna were captured, she learns. Later, her friend gale joins her to let her know that he got her family out, but district 12 was bombed into ruins by the capital in retaliation for Katniss's continued flouting of the capital's rules.