ANCIENT DISCOVERIES digs for the roots of today's war machinery. Throughout history, military requirements - killing more effectively than the enemy - have driven the leading edge of technological innovation. Almost all technology on the planet today owes its origins to inventions driven by the imperatives of war. This episode surveys the ANCIENT DEATH MACHINES that have left a legacy on today's battlefield. From apocalyptic skyscraper siege machines to ancient landmines and flamethrowers which had the potential to extinguish hundreds of lives in minutes, ANCIENT DISCOVERIES puts the lethal tech of yesterday to the test.