Along the way, Jon meets psychopaths, those whose lives have been touched by madness and those whose job it is to diagnose it, including the influential psychologist who developed the Psychopath Test, from whom Jon learns the art of psychopath-spotting. A skill which seemingly reveals that madness could indeed be at the heart of everything . . .

Combining Jon’s trademark humour, charm and investigative incision, The Psychopath Test is both entertaining and honest, unearthing dangerous truths and asking serious questions about how we define normality in a world where we are increasingly judged by our maddest edges.

‘I began The Psychopath Test late at night, tired, dispirited and ill – then found myself laughing like the proverbial loon for page after page’ Will Self, Guardian

‘The belly laughs come thick and fast – my God, he is funny . . . Ronson’s new book is provocative and interesting, and you will, I guarantee, zip merrily through it’ Observer