Raksha Dave and Alex Langlands search for the remains of a First World War stable at Catterick Garrison in North Yorkshire, where thousands of horses would have been housed and trained for the front line. They join a team comprised of archaeologists and the military attempting to uncover the role this building played in the war effort. They also visit Britain's oldest cavalry regiment, examining tools that soldiers would have used to look after their steeds, and hear the story of Warrior, known as the horse the German's could not kill.