Mockingjay by Susanne Collins

Mockingjay is the third installment of The Hunger Games trilogy by Susanne Collins. Mockingjay was released on August 24, 2010, with an initial print run of 1.2 million copies which was bumped up from 750,000 copies. The Mockingjay audio book was released simultaneously. The e-book of Mockingjay was released on August 18, six days earlier. The novel Mockingjay is preceded by 2008's The Hunger Games and 2009's Catching Fire.
Mockingjay was first released in the US and Canada on August 24, 2010. The UK, New Zealand and Australia received the book Mockingjay one day later on August 25, 2010. The Mockingjay audio book was released simultaneously on August 24, 2010.
After her rescue by rebels, Katniss reluctantly agrees to become "the Mockingjay", a symbol of the rebellion against the Capitol. As part of a deal, she demands that the leader of District 13, President Coin, grant immunity to all of the victors of the Hunger Games. She also demands the right to kill President Snow herself.
In a daring rescue, Peeta and other victors are rescued from the Capitol. However, Peeta has been brainwashed into hating Katniss, and tries to kill her upon their reunion in District 13.
The rebels take control of the districts and finally begin an assault on the Capitol itself, which Katniss is a part of. However, an assault on a "safe" Capitol neighborhood goes wrong, and Katniss and her team flee further into the Capitol with the intent of finding and killing President Snow. (Summary by Wikipedia)