Slow Horses, by Mick Herron

Slough House is where British Intelligence agents who have messed up or transgressed are sent to pasture. Burning with resentment at being set up to fail, River Cartwright wants to get his teeth into some real work and prove that he belongs in the inner sanctum in London’s Regent’s Park. But he has only been retained by the service at all because of his legendary grandfather’s influence. When a young man is kidnapped by terrorists threatening to behead him on a livestream, River and his fellow ‘slow horses’ are inadvertently drawn into the intelligence operation. Can they overcome their dodgy pasts to make an impact on the case? That will depend on whether their horrible old-school chief, Jackson Lamb, can outwit the ruthless Regent’s Park suit, Diana Taverner. Herron paints a chillingly grim and believable picture of the modern intelligence services, leavened with wry humour. The books have recently been made into an acclaimed TV series starring Kristin Scott Thomas and Gary Oldfield.