The New York Times has introduced a documentary audio series that follows Rukmini Callimachi, who covers terrorism for The Times, on her quest to understand ISIS. Today, as a special episode of \u201cThe Daily,\u201d we offer Chapter 9, Part 1 of \u201cCaliphate,\u201d in which Rukmini speaks to an ISIS detainee who challenges her to find the girl he enslaved. For more information about the series, visit nytimes.com/caliphate.\n\nThis episode includes disturbing language and scenes of graphic violence.