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 “The Daily,” we offer Chapter 4 of “Caliphate,” in which a new recruit proves his worth and gets invited to a secret meeting. For more information about the series, visit nytimes.com/caliphate.

This episode includes disturbing language and scenes of graphic violence.

Subscribe today at nytimes.com/podcasts or on Apple Podcasts and Spotify. You can also subscribe via your favorite podcast app here https://www.nytimes.com/activate-access/audio?source=podcatcher. For more podcasts and narrated articles, download The New York Times app at nytimes.com/app.

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