This program focuses on the fastest, largest, and tallest trains. We take a brief look at the steam era -- at the Mallard and the huge Big Boys of the Union Pacific railways and a more detailed look at the trains of today -- in particular the French TGV with its top speed of 320 mph. We investigate breaking systems, on-board computer systems and the latest in hi-tech tracks. We show some of the spectacular train crashes and disasters across time and take the audience on a time-lapse trip from London to Paris. Finally, we look at plans for the future with NASA's Maglifter concept -- a launch lift for tomorrow's space train.

• Jeremy Clarkson
• William Hootkins