What is the plot in cinderella man?

During the Great Depression, ex-boxer James J. Braddock (Russell Crowe) works as a day laborer until his former manager Joe Gould (Paul Giamatti) offers him a one-time slot against a rising young contender. After he wins a shocking upset, Braddock goes back into the ring full time, against the wishes of his frightened wife, Mae (Renée Zellweger). Dubbed "The Cinderella Man" for his rags-to-riches story, Braddock sets his sights on the defending champion, the fearsome Max Baer (Craig Bierko).

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