Clown Town, by Mick Herron

Slow Horse River Cartwright is still waiting for medical clearance to return to MI5’s Slough House repository for failed spies, following his Novichok poisoning. Meanwhile Louisa is considering an opportunity to go private. All plans are disrupted by First Desk Diana Taverner’s need to address a threat from the past and at the same time rid herself of her bête noir, Johnsonesque ex Tory Minister and constant troublemaker Peter Judd. As usual her machinations put the Slow Horses in the line of fire and it is up to their boss, the execrable Jackson Lamb, to sort it out. The action jumps around multiple points of view within chapters, which can get confusing. Herron has never been afraid to kill off his horses, but the long drawn out teaser as to which has been put down this time is an unnecessary and annoying cliffhanger. His withering and succinct analysis of the current state of UK politics and the intelligence service is chilling confirmation of the book title.