In this episode, the team head to the South Devon Railway to explore the life of the branch line before the Beeching cuts of the 1960s. Ruth hand-milks a local breed of cow and discovers how the railways came to the rescue when a deadly disease wiped out almost the entire stock of London cattle.
After undergoing an eyesight test, Victorian-style, Peter joins the footplate crew on the South Devon line. But it is not all plain sailing when it comes to driving the milk train through the night. We meet Dave Knowling, a steam-engine driver of 63 years' experience, who shows Peter how it is done and why it is so important to keep one eye closed when shovelling coal. Working on the Victorian railways was dangerous - 500 lost their lives and 16,000 were injured in one year alone. Ruth discovers those who lost a limb on the Great Western Railway were catered for by a special prosthetic limbs workshop.
Alex and Peter take a trip to Strathspey Railway and find out about one of Scotland's most lucrative exports, while at the Gwili Line, Ruth finds out why a young, Welsh entrepreneur became the first person to introduce mail order catalogues - thanks to the railways.