
This is the third book in Mick Herron's "Slow Horses" series, detailing the continuing misadventures of the disgraced-but-still-technically-MI5 spies headquartered at Slough House. Headed up by the semi-dissolute (and also disgraced) Jackson Lamb. I got a chuckle out of this description:
It's said of Churchill that he'd catnap in an armchair with a teacup in his hand, and when he dropped off the noise of the cup hitting the floor would wake him. He claimed this was all the rest he needed. Jackson Lamb was much the same, the difference being he used a shot glass rather than a teacup, and didn't wake when it fell.
Season Three of the TV show was based on this book, and there were some differences, but they got pretty close. The main plot driver: one of the Slow Horses, probably the one with the fewest character flaws, Catherine, gets kidnapped off a London street. Why? Her kidnappers demand that River Cartwright (another S.H.) invade MI5 headquarters and filch a revealing file from their archives.
Things don't go well for River, but as it turns out, that file is not what the bad guys wanted anyway. Nothing is quite what it seems at first. Or even second.
I plan to keep reading the book series in order, even it it means that I'll read the books before they make shows out of them. As a consumer note, I recommend reading books one and two before this one.