Designed by Oliver Bulleid for the Southern Railway, although the prototype was not completed until after nationalisation, the 'Leader' class was revolutionary. The locomotives had an unusual configuration with two power steam bogies, utilising sleeve valves and chain drive rather than more conventional valve gear. The body was streamlined, looking more like a diesel locomotive than a conventional steam engine. Initially, five locomotives were to be constructed but only one, No 36001, was completed. This was exhaustively tested and was found to be wanting in a number of areas. Amongst the faults reported, the reversing gear often jammed and the drive and valve chains stretched over time making operation unpredictable. In addition, the fireman's compartment was small and cramped and was occasionally invaded by flames from the firebox! When in 1952 the press reported the demise of the project at a cost of some #500,000, it was widely regarded as a disaster, an impression that has persisted to this day. For more than two decades Kevin Robertson has been investigating the history of the 'Leader' project.

During these years he has amassed a vast amount of information about the locomotives and the story that he is now able to reveal will rewrite the history of the project. Over the years, information has come to light from a variety of sources, including the first-hand accounts of those directly involved in the project, which shows that whilst the locomotive did have its flaws, it was by no means a complete disaster. Indeed, there is evidence to suggest that there were direct instructions from the highest echelons to ensure that the 'Leader' class failed. The British Transport Commission had seen the future and that future did not involve steam. Anything that suggested that steam could be modified and improved was therefore anathema to the authorities and was to be discouraged. With the benefit of hindsight it may well be that Bulleid was right and steam power did have a future. In The Leader Project Kevin Robertson brings together the information from his earlier books on the subject and combines this with the fruits of his most recent researches to provide the definitive account of the 'Leader' project. Alongside his comprehensive text, the book also includes a number of photographs covering the construction and testing of the class.