This book details the first 40 years of SIS, or as it’s better known MI6, history. It was commissioned by MI6 and written by historian Keith Jeffrey, who was given full access to their archives. Well full access by secret service standards, so only in so far as it doesn’t compromise national security or people involved. Though so long after the facts the bigger problem proves the lack of archive. Whether simply never created or destroyed at a later date, keeping the service secret means as little paperwork as possible.
Sadly this means that a lot of story can only be traced through the numbers involved. How many people were stationed where, when and especially: how much it all cost. This made the book really boring to at times and I admit to skipping over parts that were mainly this. On the plus side if you want all the details, this book certainly has them. Luckily there are plenty of fun parts in between this. Details of the duties of technical departments, anecdotes about agents in the field and extracts from letters and diaries are really fun to read.
So if you’re really into MI6, history in general or are researching the subject this is the book for you. If you just want to read some fun real life spy stories, perhaps look around for another book.