The app Truecaller estimates that as many as 56 million Americans have fallen foul to scam calls, losing nearly $20 billion.

Enter L., an anonymous vigilante, referred to here by his middle initial, who seeks to expose and disrupt these scams, posting his work to a YouTube channel under the name “Jim Browning.”

On today’s Sunday Read, Yudhijit Bhattacharjee follows L.’s work and travels to India to understand the people and the forces behind these scams.

This story was written by Yudhijit Bhattacharjee and recorded by Audm. To hear more audio stories from publishers like The New York Times, download Audm for iPhone or Android.

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