The most fearsome tank on today’s battlefield is the US M-1A2 Abrams, virtually impregnable, fast, and capable of destroying an opponent many miles away. It is the most perfect example of a weapons race which began over 90 years ago to find a fighting machine capable of breaking the stalemate of the World War 1 trenches. The programme looks at how these behemoths were shaped in combat; how the competing requirements of protection, cross-country ability and firepower were refined; and how tactics such as Blitzkrieg were developed to make the Battletank King of the Battlefield.