Madness Inc and Jon Ronson should have been made for each other. A gifted writer and sometime comic broadcaster (think of a squeaking Louis Theroux), Ronson’s niche in the market is the hack with the off-the-wall take. He is the author of the bestselling The Men Who Stare at Goats, which was made into a boring film, and he made a funny – both ha-ha and peculiar – investigation into David Icke’s belief that Prince Philip and the rest of the royals are, in fact, shape-shifting lizards from outer space who eat children. Being off the wall, Ronson cosies up to Icke and his lizards and you’re left befuddled. It could explain the Duke of Edinburgh, mind. In The Psychopath Test Ronson finds himself on an utterly compelling and often unbelievable adventure into the world of madness. Or, at least, that’s what the puff says.

The general thrust is to question doctors’ categorisation of madness and lift a sceptical eyebrow at the power of psychiatrists to ordain some people as psychopaths and lock them away. That’s a worthy subject. Bad psychiatrists exist, and terrible things have been done to the innocent – sane