Nobody Walks, by Mick Herron

Tom Bettany has been estranged from his son, Liam, since his wife died four years earlier. He is down and out, working in an abattoir in in France when he is notified that Liam has died in an accidental fall. Back in London for the funeral, Bettany embarks on a quest to discover exactly how his son died and who might be responsible. Unfortunately this sparks the interest of his former employer, MI5, never a good thing. Then there are the remnants of an organised crime gang that was the target of his undercover operation in this former employment. There is no possible good outcome here, in a situation from which nobody walks away. Another tale that is Slow Horses adjacent, this one gives the origin story of J.K. Coe – what led to his PTSD and banishment to Slough House. It can stand alone, but knowledge of the Slough House world adds breadth and depth. It also shines a light on the conduct and motivations of former service head Dame Ingrid Tearney, which provides an interesting counterpoint to that of later successor ‘Lady’ Di Taverner. This is a gripping thriller, with all the grim violence of the Slow Horses novels but maybe lacking their sardonic edge that can serve to leaven the darkness.