1. The Mocking Jay Pin
In the movie, Katniss finds the Mocking Jay pin at The Hob, where it's given to her by a gypsy-like lady -- but in the book, the Mocking Jay pin was a gift given by Madge, the daughter of District 12's mayor. This poses many questions for the following movies, because the Mocking Jay pin ends up becoming such a critical symbol to Panem.
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