Monkey on My Back (1957)
Monkey on My Back is a 1957 biographical film noir starring Cameron Mitchell as Barney Ross, a world champion boxer and World War II hero (based on a real-life titleholder). The movie is heavily fictionalized, but both the movie character and the biographical character become addicted to opiates due to war conditions. In the climax of the film, Ross faces a challenging battle to recover from his addiction.
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