In his 22-year career in the FBI, undercover agent Scott Payne infiltrated some of the most dangerous criminal and extremist groups in America, from a motorcycle gang called the Outlaws to a white-supremacist group known as the Base. Payne shares his firsthand case accounts of gathering intelligence and stopping illegal activity in his memoir, Code Name: Pale Horse; How I Went Undercover to Expose America’s Nazis. His story is also featured on the latest season of the Slate podcast White Hot Hate. Payne sat down with Apple News In Conversation host Shumita Basu to talk about some of his most harrowing moments on the job and the growing threat of extremism in the U.S.