Could the event that triggered the `war to end all wars' have been prevented? The shot that killed Archduke Franz Ferdinand - long considered the catalyst for the outbreak of the First World War - is often described as the `shot heard around the world'. Far less widely known is the fact that the Archduke may have owned, but on that fateful day did not wear, a silk bulletproof vest created by Polish priest-turned-inventor Casimir Zeglen.

Applying innovative new research, Lisa Traynor highlights the risks associated with power and status in the early 20th century, and charts the technological development of pistols used in the period's assassination plots. Testing replicas of Zeglen's invention with a Royal Armouries Browning Model 1910 pistol identical to that used by the Archduke's assassin, Traynor poses the haunting question: if Franz Ferdinand had worn body armour on the day of his assassination, would it have saved his life?

Featured in the BBC TV series Sword, Musket and Machine Gun: Britain's Armed History, this fascinating book breaks new ground in our understanding of arms and armour technology on the eve of the First World War.