The Notting Hill Mystery (1862–63) is an English-language detective novel written by an anonymous author using the pseudonym "Charles Felix", with illustrations by George du Maurier. The author's true identity was never formally revealed in his lifetime but several critics have since suggested that it was Charles Warren Adams (1833–1903), a lawyer who wrote a few novels under a pseudonym. The novel was revolutionary in its techniques and style and has been called the first detective novel.