What is it about the steam locomotive that exerts such a pull on the emotions? No other of mankind's inventions has endeared itself to the heart in the same way as the steam engine; no other seems quite so alive, showing its power so dramatically. The power of steam can be seen in so many ways. Whether it's streamlined express, a slow heavy goods train or a compact colliery engine blasting up seemingly impossible slopes, all display their power through clouds of smoke and steam. No other machine comes to life so well on screen; it is almost as if film was invented to show the steam engine in motion and this programme captures the raw power of steam locomotives at work. From the heyday of their working lives, using archive film, to contemporary footage of those great machines which are still with us today, this film explores the steam locomotive at work throughout Great Britain, each one a portrait of the power of steam.