The strategic importance of trains has resulted in many elaborate schemes and methods being devised to destroy them. Historian Neil Faulkner tells the story of Lawrence of Arabia and his pioneering guerrilla warfare against the railways of the Ottoman Empire. We track down a train used by the SOE in the Second World War to teach their agents how to de-rail locomotives. Under New York's Grand Central Terminal is a railway secret: a generator called M42 that its claimed Nazi spies tried to destroy in the Second World War. Under New York's Waldorf Astoria is another secret: rusting in a siding is President Roosevelt's personal train that brought him secretly into the city.

Between 1939 and 1945 war came to Britain's railways. By now an established technology, in the Second World War trains operating in Britain came into their own - bringing troops back home after the humiliation of Dunkirk, as well as taking hundreds of thousands of city children to safety. The programme interviews eye-witnesses to both railway adventures, and discovers the disused Tube station where the evacuations were coordinated. There are tales of the heroism of the railway staff during the Blitz, and how a small siding in a Hampshire railway station played its part in the preparations for D-Day.