During World War II, a fiery phenomenon terrorizes American airmen in the night skies over Europe. The pilots call these fireballs “Foo Fighters,” and swear they move at over 200 mph and defy the laws of physics. But what are they? What’s the hidden truth behind the mysterious Foo Fighters of World War II? Watch all new episodes of History's Greatest Mysteries on Mondays at 9/8c, and stay up to date on all of your favorite The HISTORY Channel shows at history.com/schedule. #HistorysGreatestMysteries Subscribe for more from History's Greatest Mysteries and other great The HISTORY Channel shows: http://histv.co/SubscribeHistoryYT Find out more about the series and watch full episodes on our site: http://histv.co/HistorysGreatestMysteries Check out exclusive The HISTORY Channel content: History Newsletter - www.history.com/newsletter Website - http://www.history.com Facebook - https://www.facebook.com/History Instagram - https://www.instagram.com/history TikTok - https://www.tiktok.com/@history The HISTORY® Channel 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. History’s Greatest Mysteries is a one-hour documentary series that examines the top theories surrounding the world’s most enigmatic unsolved mysteries. Hosted and narrated by Academy Award® nominee and Emmy Award® winner Laurence Fishburne, each episode unpacks these puzzles with contributions from top historians, authors, scientists, and researchers. From unsolved crimes to lost and buried treasures, and the deaths and disappearances of famous figures, History’s Greatest Mysteries will explore possible explanations to some of the world’s most confounding events. 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.