The Locomotives of Robert Riddles guides the reader in the quest to understand how Robert Riddles career on the LMS and in war service shaped his knowledge and character and led to him becoming the obvious choice for leading the locomotive engineering function within the newly-formed Railway Executive. The book outlines the substantial impact Riddles had on the design and supply of locomotives that were to support the Allied military campaigns in the second world war, including useful analysis of the types of locomotives specifically designed for that work. The bulk of the book outlines the decision-making processes that led to the twelve designs of standard steam locomotives that were intended to be the future stop-gap before electrification, and the political and practical reasons for successive policy changes that led to their unexpectedly short lives. Those events include the 1955 Modernization Plan with its emphasis on dieselization, and the subsequent railway rationalizations that reduced the need not only for new steam locomotives but also made relatively new diesels redundant. Each BR standard locomotive type is described in its own chapter. The performance of each class is given its rightful emphasis. The book is comprehensively illustrated with largely unpublished pictures that cover a wide range of locations and locomotive duties.