This is a very enjoyable book. It is very well-written by an intelligent, deeply knowledgeable author who knows how to tell a good story, and it brings the historical events and characters fascinatingly to life.
The first section of the book (nearly half of it) is a terrific potted biography of Isaac Newton, with a really good, comprehensible account of his character, intellectual development and achievements. I am a physicist by training, I have also studied History of Science and have read a great deal about Newton, some of which has been very good and some very bad. This is one of the best short accounts I have ever read - incisive and compellingly readable, it gives a really good insight into the man, the way he worked and what motivated him. On the second page, by the way, Levinson writes, "psychoanalysis at a distance of centuries is a fool's game." I was pretty sure I was in safe hands after reading that, and I was right.
All this is essential for understanding Newton's time at the Mint and his approach to the pursuit of counterfeiters. This story is also brilliantly told, with a fascinating, wonderfully accessible account of the economic problems of the time, how the coinage contributed to them and the birth of money as we know it (or think we know it) today. This is wrapped up in an enthralling narrative of, effectively, a detective pursuing a criminal and the cat-and-mouse tactics each employed.
I often find that biography or history struggles to hold my interest and attention for hundreds of pages. This did - it was scholarly, fascinating and thoroughly engaging. I found it had the effect of a really good novel, leaving me very keen to get back and read some more, and I recommend it in the strongest terms.