Spy Line

 is the fifth novel in the Bernard Samson series, not counting the historical prequel Winter.

 Standout quotes include 

‘Failure in the art of intelligence comes to those who cannot distinguish between what they know to be facts, and what they wish were true’ [Silas Gaunt to Bernard Samson, Spy Line Chapter 15]

Commentary
A Spy Hook, Spy Line and Spy Sinker (Trilogy) trilogy was published.