With his hazy command of forensics and his restless scouring for clues, the detective is an archetypal mid-Victorian figure, reflecting the inquisitiveness of an age seeking to extend the boundaries of knowledge.

Policemen, such as the Bow Street Runners and Robert Peel’s ‘Bobbies’, had, of course, been around much longer. But their methods were crude, and the methodical, evidence-sifting detective only surfaced in 1842, when the Metropolitan Police, concerned at criminals’ unhindered ability to operate across the borders of its various London districts, set up a small, centralised detective division at Scotland Yard.

Reports of these new foot soldiers in the war against crime began creeping into newspapers and even fiction, but it was not until ten years later that the first proper detective appeared in literature in the form of Inspector Bucket in Dickens’s Bleak House. (In the meantime Edgar Allan Poe