The third movie The Hunger Games series takes place in District 13 - the forgotten district that once was destroyed by the Capitol for their uprising-worthy opinions and personalities. Well, we find out in this movie that that is not the case. District 13 was able to build up from the rubble, a living quarters that is under ground and unseen from the Capitol. After being extracted from the arena, Katniss and Finnick are taken to to District 13 to recuperate and eventually aid in the attacks on the Captiol. Unfortnately, Peeta is being held captive by President Snow in hopes that it will end the uprisings.
In this part 1 of the Mockingjay, Katniss must become the Mockingjay symbol that everyone already thinks she is. It doesn't come easy to her, as I'm sure most of you know from watching the first two movies. She doesn't really do what she's told very well. But once she sees what the Capitol did to District 12 (her district) and the poor wounded survivors in the hospital in District 8, she will be the Mockingjay that everyone needs. They film propos to get everyone in the other districts behind them on their quest to take down the Capitol.
In the end, District 13 is able to extract Peeta, Annie, and Johanna from the Capitol and bring them back to their loved ones. There is one twist thought (SPOILER ALERT), Peeta has been brainwashed by the President (which I mentioned before) and he believes that Katniss is trying to kill him. Therefore - he tries to kill her first. And this is where it ends. I totally called that this would be where they ended the first movie part, it's the perfect place and provides a cliffhanger into Mockingjay Part 2.
"If that boy were an apple, he'd be a delicious"