French Connection II (1975)

This sequel to William Friedkin's 1971 crime drama finds Detective "Popeye" Doyle (Gene Hackman) still hot on the trail of slippery drug trafficker Charnier (Fernando Rey), but this time in Marseilles, France. Uprooted from his familiar New York City beat, Doyle struggles to assert himself in a strange city and break the drug ring wide open. When Charnier's goons force him into a heroin addiction, the tough cop must summon every ounce of his courage to kick the habit cold turkey.