Given the question: Build a movie plot around this: Who double crosses Grandi? Quinlan
The answer is:
While passing through the seedy border town of Los Robles, newlyweds Mike and Susan Vargas (Charlton Heston and Janet Leigh) witness a car bomb explosion in which Rudy Linnekar, a local construction magnate, and his female companion are killed.Suspecting that the bomb was planted on the Mexican side of the border and may be the work of the Grandi narcotics ring, Vargas, the Mexican head of the Pan-American Narcotics Commission, offers his assistance to the Los Robles officials investigating the case. The lead detective, the obese and lumbering Capt. Hank Quinlan (Orson Welles), rudely rebuffs Vargas' offer. However, Quinlan's partner, the loyal Sgt. Pete Menzies (Joseph Calleia), and Adair, a district attorney (Ray Collins), apologize for Quinlan's behavior and invite Vargas to observe their investigation because of his status as a highly placed Mexican government official.In the meantime, a group of young Mexican men working for "Uncle" Joe Grandi (Akim Tamiroff), a small-time crime boss with a bad toupee, bring Susan, an American, to Grandi's headquarters in a sleazy hotel. Grandi warns Susan of dire consequences if her husband continues his prosecution of Grandi's brother, an imprisoned drug dealer awaiting trial in Mexico, but Susan is unimpressed.While investigating the case on the Mexican side of the border, Quinlan visits the tawdry brothel run by Tanya, a former lover (Marlene Dietrich), and the place fills him with nostalgic yearnings. Upon learning of Susan's encounter with Grandi, Vargas decides that she will be safer stashed in a motel on the American side of the border while he continues working on the Linnekar case. However, unknown to Vargas, the motel is owned by Grandi, staffed by a very nervous night clerk (Dennis Weaver), in the middle of the desert.Quinlan soon tracks down a suspect, a Mexican shoe clerk who was having an affair with Linnekar's daughter, Marcia (Joanna Moore), and later married her in a secret ceremony. Sanchez (Victor Millan) claims he is innocent and appeals to Vargas...