This book is an exploration of the industrial archaeology of Britain's 'atomic age': the physical traces of what remains and what has been lost of this endeavour. To many in the generation of post-war readers of broadsheet newspapers, the technical press, 'boys' own' comics, and viewers of upbeat cinema newsreels, the industry's early leaders - the 'nuclear knights', William Penney, John Cockcroft and Christopher Hinton - were household names. The places associated with this venture, secured by high fences, became symbols of a new industrial age. Aldermaston, Dounreay, Harwell, Windscale, and Winfrith were locations where science fiction became reality for some, while others viewed them as home to some 'unmentionable devilment'. Their silhouettes were celebrated on postage stamps, proclaiming to the country and the world Britain's mastery of the atom. Today, these relics of late 20th century science and industry are being decommissioned and largely erased from the landscape.