I’d highly recommend Most Secret War which covers the role of Scientific Intelligence in Britain’s battle with Germany during WWII.

https://www.amazon.com/Most-Secret-Penguin-World-Collection/...

Dr. R.V. Jones had significant involvement in the War of the Beams, and after the war wrote a book about British Scientific Intelligence efforts during the war.

https://www.amazon.com/Most-Secret-Penguin-World-Collection-...

Here's an US Amazon.com entry: http://www.amazon.com/Most-Secret-Penguin-World-Collection/d... Based on a review comment and the page count it looks like it's a version of The Wizard War I cited in another posting in this topic.

Lots of inexpensive used paperback editions available.