London Rules might not be written down, but everyone knows rule one. Cover your arse. Regent's Park's First Desk, Claude Whelan, is learning this the hard way. Tasked with protecting a beleaguered prime minister, he's under attack: from the showboating MP who orchestrated the Brexit vote; from the showboat's wife, a tabloid columnist; from the PM's favourite Muslim, who's about to be elected mayor of the West Midlands; and especially from his own deputy, Lady Di Taverner. Over at Slough House, the crew are struggling with personal problems. But collectively, they're about to rediscover their greatest strength - that of making a bad situation much, much worse. It's a good job Jackson Lamb knows the rules. Because those things aren't going to break themselves.