Deep beneath the streets of London sit thousands of highly classified and previously top-secret government files which disclose the details of extensive military, spy agency and police investigations into the paranormal.With hundreds of hours dedicated to examining these formerly off-limits documents from the National Archives, investigative journalist Tim Tate reveals just how far authorities on both sides of the Atlantic were willing to go to venture into the unknown.Combining his findings with expert insight from Dr David Clarke, Britain's X-Files fact-checks out-of-this-world phenomena with cases including the legend of the Flying Dutchman, Harry Grindell Matthews and his Death Ray, the Beast of Bodmin, Uri Geller, the Comet plane catastrophes, premonitions on the Aberfan disaster and more.