When her daughter Karen was kidnapped in 2014, Miriam Rodríguez knew the Zetas, a cartel that ran organized crime in her town of San Fernando, Mexico, were responsible.

From the hopelessness that her daughter may never return came resolve: She vowed to find all those responsible and bring them to justice.

One by one, Ms. Rodríguez tracked these people down through inventive, homespun detective methods.

Today, we share the story of her three-year campaign for justice.

Guest: Azam Ahmed, The New York Times’s bureau chief for Mexico, Central America and the Caribbean.

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Background reading: 

• Armed with a handgun, a fake ID card and disguises, Miriam Rodríguez was a one-woman detective squad, defying a system where criminal impunity often prevails. Read Azam's full story (also available in Spanish here).

For more information on today’s episode, visit nytimes.com/thedaily. Transcripts of each episode will be made available by the next workday. 

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