Why are they blasting Iraqi prisoners-of-war with the theme tune to Barney the Purple Dinosaur? And why have 100 de-bleated goats been secretly placed inside the Special Forces command centre at Fort Bragg, North Carolina? In 1979 a secret unit was established by the most gifted minds within the US Army. Defying both military practice and the laws of physics, they believed a soldier could become invisible, pass through walls and, perhaps most chillingly, kill goats just by staring at them. With first-hand access to the leading players in the story, Ronson has traced the evolution of these bizarre activities over the past three decades, and poses questions no-one else has yet dared to ask about which of them — and more — are happening still.