Learn more about the psychological warfare used in Vietnam, in this scene from Season 1, Episode 5, "Mind Games." Watch new episodes of Secrets Declassified with David Duchovny Fridays at 10/9c; and stay up to date on all of your favorite The HISTORY Channel shows at history.com/schedule. #SecretsDeclassified Subscribe for more Secrets Declassified and other great The HISTORY Channel shows: http://histv.co/SubscribeHistoryYT Check out exclusive The HISTORY Channel content: History Newsletter - https://histv.co/newsletter Website - https://histv.co/History Facebook - https://histv.co/Facebook Instagram - https://www.instagram.com/history TikTok - https://www.tiktok.com/@history From black ops and bizarre experiments to deadly cover-ups and nefarious gadgets, David Duchovny pulls the curtain back on all the government secrets in modern history we always suspected, but were never given the answers to. Through the strange and shocking things countries the world over - and those who work for them - have done in the name of national interest, we'll investigate the explosive evidence from newly declassified files that will finally shine a new light on what's really going on deep in the shadows. HISTORY® is the leading destination for award-winning original series and specials that connect viewers with history in an informative, immersive, and entertaining manner across all platforms. The network’s all-original programming slate features a roster of hit series, premium documentaries, and scripted event programming.