Monkey on My Back (film)

Monkey on My Back is a 1957 biographical film starring Cameron Mitchell as Barney Ross, a world champion boxer and World War II hero based on a reallife 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.

Cathy, a single mom of a young girl, Noreen, gets to know Barney, but is unaware of his gambling habit. When he loses to Henry Armstrong, he owes thousands to a bookie named Big Ralph and is forced to work in Ralphs bar to pay off the debt.Barney joins the Marines when war breaks out. He gets Cathy to marry him before leaving for the South Pacific, where, at 33, his heroism at Guadalcanal saves another soldiers life and earns Barney a medal, the Silver Star. But he also contracts malaria, for which a medic prescribes morphine. ........

Source: Wikipedia