This book is a fantastic overview of the racing cars built by Lotus, from the original cars built by Chapman, up to the racing version of the Esprit in the mid 90's.
Beginning with the original hill-climb cars, each of the models has some description and list of it's racing history, which for some models includes almost a full racing history in the case of the of the marque's more famous formula one cars, such as the 25, 49, 78 and 79, as well as the company's sports racing cars. Small stories and anecdotes are commonplace, and interviews with some members of the Lotus team give insight into the ideas and people behind the cars.
If you're looking for an in-depth report on a single model, this might not be the book you're looking for (particularly if you're interested in the Seven), but as an overview for someone interested in the topic, this book is unique.