Chris examines how trains transformed Britain. He begins in the cab of Puffing Billy the world's oldest surviving steam locomotive, built in 1813. He also tells the story of the navvies who built the railways.

Chris examines the role the railways played during the two global conflicts of the 20th century. As well as keeping vital supply lines open they evacuated children and provided underground air raid shelters.

The series concludes by examining the devastating impact of the Beeching report, which led to half of all stations and nearly a third of lines in Britain closing and at the reinvention of the railways for the modern age.