The Notting Hill Mystery was first published between 1862 and 1863 as an eight-part serial in the magazine Once a Week, written under the pseudonym Charles Felix. It has been widely described as the first detective novel, pre-dating as it does other novels such as Wilkie Collins’s The Moonstone (1868) and Emile Gaboriau’s first Monsieur Lecoq novel (1869) that have previously claimed that accolade. The story is told by insurance investigator Ralph Henderson, who is building a case against the sinister Baron ‘R___’, suspected of murdering his wife in order to obtain significant life insurance payments. 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 in the form of diary entries, family letters, chemical analysis reports, interviews with witnesses and a crime scene map, the novel displays innovative techniques that would not become common features of detective fiction until the 1920s. Now made available again, with George du Maurier’s original illustrations included for the first time since the original serial publication, this new edition of The Notting Hill Mystery will be welcomed by all fans of detective fiction.