With all of the black-and-white moralizing in our world today, we decided to bring back an old show from 2011 about the little bit of bad that's in all of us...and the little bit of really, really bad that's in some of us. Cruelty, violence, badness... in this episode we begin with a chilling statistic: 91% of men, and 84% of women, have fantasized about killing someone. We take a look at one particular fantasy lurking behind these numbers, and wonder what this shadow world might tell us about ourselves and our neighbors. Then, we reconsider what Stanley Milgram's famous experiment really revealed about human nature (it's both better and worse than we thought). Next, we meet a man who scrambles our notions of good and evil: chemist Fritz Haber, who won a Nobel Prize in 1918...around the same time officials in the US were calling him a war criminal. And we end with the story of a man who chased one of the most prolific serial killers in US history, then got a chance to ask him the question that had haunted him for years: why? EPISODE CREDITS: Reported by - Pat Walters and Latif Nasser Produced by - Pat Watlers with help from - Carter Hodge. Signup for our newsletter!! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up (https://radiolab.org/newsletter)! Radiolab is supported by listeners like you. Support Radiolab by becoming a member of The Lab (https://members.radiolab.org/) today. Follow our show on Instagram, Twitter and Facebook @radiolab, and share your thoughts with us by emailing radiolab@wnyc.org. Leadership support for Radiolab’s science programming is provided by the Simons Foundation and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.

Plus, how human psychology might play a role.

Harriet Clark’s new novel “The Hill” parallels her own childhood years spent visiting the prison where her mother was incarcerated. She talks with Rachel Aviv.

Mayor Mamdani filmed a video in front of the most expensive penthouse ever sold in the United States to celebrate a new tax on luxury second homes. It went viral, and the city's billionaires were not happy. WNYC reporter Elizabeth Kim takes us from Billionaire's Row to Fordham Road in the Bronx to speak to New Yorkers about the fight to tax the rich. Photo: Michael Lee/Moment via Getty Images -Got any questions, comments or story ideas? Send us a message at NYCNow@WNYC.org