Brad Beeler spent 25 years as a Secret Service agent protecting presidents and interviewing thousands of people accused of crimes. He reveals the surprising truth: people tell you the truth when they feel safe, not cornered—and a single raised eyebrow of contempt can shut down disclosure instantly. His framework for earning trust applies to interrogations, parenting, marriages, and business negotiations. Neutral facial expressions code as threatening to the brain's primitive survival instinct; positive affect is required to keep someone disclosing, not judgment or interrogation.