The idea of drug trafficking and addiction as social threats didn't emerge until the post-war years when marijuana and heroin no longer confined themselves to urban blacks and jazz musicians. Though the subject would seem a natural for film noir, the cycle as a whole ignored it, except for odd references (Jules Amthor drugging Philip Marlowe in Murder, My Sweet, for example).
But in the late 1940s, two films took on the phenomenon directly: Port of New York and To The Ends of the Earth. Both films show the stridency that would soon come to be characteristic of the Red Scare films of the early 1950s. Port of New York, however, effectively explored its noirish milieu, while To The Ends of the Earth harks back to the international espionage pictures of wartime and the pre-war years.
Treasury agent Dick Powell witnesses the mass death of Asian `slaves,' jettisoned overboard in chains from a Japanese freighter off the coast of San Francisco. Soon, in relentless pursuit of the opium poppy, Papaver somniferum, he circles the globe from Shanghai to Egypt to Cuba and finally to New York. His travels curiously intertwine with those of an American widow (Signe Hasso) and her young Chinese ward (Maylia). He uncovers a ruthless (`fanatical' is the preferred adjective) worldwide conspiracy to grow, distribute and sell opium, ultimately refined into heroin. The case doesn't crack until his ocean liner begins entry into New York harbor.
It's a good-bad movie. One of the burdens the noir cycle occasionally had to shoulder was paying homage to various principalities and duchies of the U.S. Government, generally J. Edgar Hoover's Federal Bureau of Investigation (as in Call Northside 777) or the Treasury Department (as in T-Men). Here, it's the Narcotics Bureau headed by Harry Anslinger, who graces the movie with his presence in three cameos. The requisite tone of reverence is anathema to noir, and Powell's voice-over narration drones on and on, a powerful opiate in itself.
But the nuts and bolts of the drug trade operated by a global cartel retain surprising interest, and the movie's pace picks up as it progresses, right up to a fairly shocking twist at the end. Many of its attitudes and assumptions show their age, but To The Ends of the Earth ultimately delivers its product.