What do you feel like reading, curled up in your armchair? Obviously, a whodunnit. But not just any old whodunnit. You don’t want the colourless style and arid tricksiness of Agatha Christie, nor the stately prose and rampant snobbery of Dorothy L. Sayers. You want the real queen of crime, the best, the darkest, the most interesting, idiosyncratic and literary novelist that the Golden Age of detective fiction produced. I refer, of course, to Margery Allingham.