Journalist Sam Quinones blew Marc’s mind six years ago with his book Dreamland: The True Tale of America’s Opiate Epidemic. More recently, he devoted his research and reporting to understanding how America got caught in the clutches of newer, more addictive, and more lethal synthetic drugs. Sam’s latest book is The Least of Us: True Tales of America and Hope in the Time of Fentanyl and Meth. Sam talks with Marc about how these drugs work over the brain, how they’re getting into the country, and how they have exacerbated America’s homelessness crisis.