The Notting Hill Mystery by Charles Warren Adams; The First Detective Novel?

Can you name the first detective novel ever published?

Many believe it to be Wilkie Collins's The Moonstone, published in 1868. Others speculate it might be Émile Gaboriau's first Monsieur Lecoq novel, L'Affaire Lerouge, published in 1866.

But many scholars consider Charles Warren Adams's The Notting Hill Mystery, originally published as an eight-part serial in "Once A Week" magazine in 1862 under the pseudonym Charles Felix, then as a single-volume novel in 1863 by Bradbury & Evans, to truly be the first.

The Notting Hill Mystery begins in London, where the wife of the sinister Baron R__ dies after drinking from a bottle of acid, apparently while sleepwalking in her husband's home laboratory. It looks like an accident, until insurance investigator Ralph Henderson learns that Baron R__ took out numerous life insurance policies on his wife. Henderson descends into a maze of intrigue including a diabolical mesmerist, kidnapping by gypsies, slow-poisoners, a rich uncle's will … and three murders. Presented as Henderson's evidential findings — diary entries, family letters, chemical analysis reports, interviews with witnesses, along with a crime scene map — the novel displays innovative techniques that would not become common features of detective fiction until the 1920s.

The British Library has published a new edition of this book that also includes George du Maurier's illustrations, the first edition to do so since the original publication in serial form.

The official publication date of the book in the US is April 15th, 2012, — it was published in the UK in February — but it is already available to purchase.