A couple is murdered on the US-Mexico border by means of a bomb planted in a car. The crime involves the police officials of the two countries (Welles and Charleston Heston) involved in a professional and ego war and we see a rapid fire convoluted plot which has one gripped and fascinated till the last gunshot, springing fresh surprises at each turn, not to mention the voluble, dazzling script. Welles as the American police officer elects to play a complex and larger than life persona as a committed, dissipated, overbearing and pathetic persona who is none too scrupulous about methods so long as he can put a noose around the person he intuits as guilty. The film concludes on a tragic note with the bewitching Marlene Dietrich, who is in a guest role, concluding with "He was some kind of a man. What does it matter what you say about people?"
The whole point of the film is the dramatic/cinematic genius of Orson Welles, all too pervasive even in this, his period of creative and professional decline. Its somber black and whites depicts a seamy world of drugs, crime and enforcement. The script sparkles and dances saying something unexpected each time. Ultimately it is the the beauty which is uniquely celluloidal that lifts this film far above the ordinariness of its theme. This is cinema noire--whose hallmark is a kind of fatalistic melancholia--at its headiest.