Slough House is the Intelligence Service outpost for failed spies, former high-fliers now dubbed the 'slow horses'. Catherine Standish, one of their number, worked in Regent's Park long enough to understand treachery, double-dealing and stabbing in the back, and she's known Jackson Lamb long enough to have learned that old sins cast long shadows. 

And she also knows that chance encounters never happen to spooks, even recovering drunks whose careers have crashed and burned.

What she doesn't know is why anyone would target her.

So whoever's holding her hostage, it can't be personal. It must be about Slough House. Most likely, it's about Jackson Lamb. And say what you like about Lamb, he'll never leave a joe in the lurch.

He might even be someone you could trust with your life.