This movie is a love story set in a Brave New World-type near-future where cities are heavily controlled and accessible only through checkpoints. People cannot travel unless they have "papeles" (papers in Spanish; words and sentences in many languages, especially Spanish, French, and Chinese are mixed with English in this new world), a special travel permit issued by the totalitarian government, the "Sphinx". Outside these cities, the desert has taken over and shanty towns are jammed with non-citizens, people without IDs forced to live primitive lives. William Geld (Tim Robbins) is a family man who works as a government investigator. When he is sent to Shanghai to solve a case of fake IDs, he meets a woman named Maria Gonzales (Samantha Morton). Although he realizes she is behind the forgeries, he cannot help but fall completely in love with her. He hides her crime and they have a wild, passionate affair that can last only as long as his visa: twenty-four hours. Back home, William is obsessed with the memory of Maria. When the original investigation is inevitably re-opened a week later and William is sent back to finish the work he started, he tracks her down only to discover she has been accused of a Code 46 violation, and any further relationship is therefore impossible.