Revealing mistake: When Katniss is blown back from the explosion, her stunt person is visible. This can be proven because the stuntperson's skin tone is different and her hair is not in a braid. It is in a ponytail. Wires can also be seen pulling her to give the illusion that she was blown back from the explosion. (01:33:00)
Revealing mistake: Katniss shoots and kills someone who throws a spear at Rue. When Rue says "you have to win" we see a shot of the dead bloke with the arrow sticking out of him. In this shot, if you look carefully you can see a square outline under his shirt that the arrow is stuck in. (01:36:20)
Revealing mistake: When Katniss is running from the fire bombs, when she lunges forward, you can see her stunt double's face.
Chosen answer: In the book, she left it with Peeta in case he was discovered while she was away. Apparently she was meant to have done this in the film as well, they just neglected to show it, causing some confusion.
Phixius ★