In September 1916, at the Somme, the British Army sends a machine no soldier on either side has seen before rolling toward German lines: the tank. This episode of Greatest Tank Battles reconstructs that first deployment, using battlefield reenactments, archival photographs, and expert interviews to explain why the early Mark I tanks were as likely to break down or get stuck in mud as to break through enemy trenches. It follows the German Army's scramble to counter a weapon they had no answer for, from improvised anti-tank tactics to the crash program that produced Germany's own tank, the A7V, setting up history's first tank-versus-tank battles. Historians walk through the mechanical limits of these early machines, the tactics commanders improvised on the fly, and how quickly both sides realized armored warfare had changed the battlefield permanently. The film keeps its focus narrow and technical, treating the tank less as a symbol than as flawed, experimental machinery that had to prove itself under fire.