Melvyn Bragg examines one of the greatest scientific breakthroughs of the 20th century, and certainly the most controversial; the development of nuclear physics. Harnessing the enigmatic qualities of the atom’s tiny core brought us nuclear power and gave us The Bomb, a breakthrough with such far-reaching consequences that it moved the physicist Albert Einstein to say, “Had I known, I should have become a watch maker”.How can such outlandish power be released from such infinitesimal amounts of matter and what does the science of the nucleus tell us about how our universe is built? Nuclear technology provokes strong emotional and political reactions, but what are the plain facts behind its development as a science? With Jim Al-Khalili, Senior Lecturer in Physics at the University of Surrey; Christine Sutton, Particle Physicist and Lecturer in Physics at St Catherine’s College Oxford; John Gribbin, Visiting Fellow in Astronomy at the University of Sussex.