In 2018, the British city of Salisbury crashed into newspaper headlines worldwide when former Russian military officer Sergei Skripal and his daughter, Yulia, were poisoned with nerve agents there. This was the first time that many people had heard of these deadly, yet invisible and odourless weapons being used, but the history of nerve agents goes much further back, to the interwar period and an unprofitable discovery in pesticide production. In this engrossing discussion with James Rogers, Dan Kaszeta explores the development of nerve agents under the Nazi Regime, the figures and institutions pushing them, and the reasons behind the Third Reich’s restraint from using these chemicals, despite being the only country to possess them. He also reveals the post-war continuation of nerve agent research on both sides of the Iron Curtain, and the weapon’s gradual dissipation around the world. Dan Kaszeta is a securities specialist and world expert on chemical weapons.