You could call Borderline (1950) a south of the border noir, a crime drama playing out in the cantinas, cheap tourist hotels, and dusty desert roads of Mexico and across the U.S.-Mexico border at Tijuana, where the drug trade flows into the United States.
Police woman Madeleine Haley (Claire Trevor), following a lead provided by a smuggler arrested in Los Angeles, goes undercover as a showgirl in Mexico to find the drug supplier with a taste for “cheap blondes” (Raymond Burr) and ends up on the road with American hood Johnny Macklin (Fred MacMurray). The two freelancers team up to smuggle a cache of narcotics over the border, bantering along the way while slipping from wary partners to lovers, neither realizing the other has an ulterior motive.
The low budget production, shot mostly in the California deserts and on anonymous sets playing the cheap hotel rooms and chintzy Mexican nightclub, was produced by Milton H. Bren, a former MGM executive who married Trevor in 1948. The part of Madeleine was perfect for his wife, who was no stranger to tough broads. In such classic film noirs as Murder, My Sweet (1944), Raw Deal (1948), and Key Largo (1948), she played women who had gotten knocked around and scuffed up by life. In the opening scenes of Borderline she comes on more like an excitable cub reporter than a veteran officer and a former O.S.S. agent in her first scenes. At least until she hits Mexico and slips into character as a cheap American bar girl, a woman barely talented enough to land a job dancing in a Mexican nightclub as a chorus girl. Once in character, she rolls with the punches with the best of them, playing the cheap blonde in front of Johnny while snapping evidence with her hidden camera while his back is turned.
Plays on TCM on Wednesday, August 7