The Wold Newton family is a literary concept derived from a form of crossover fiction developed by the American science fiction writer Philip José Farmer. Farmer suggested in two fictional biographies (Tarzan Alive: A Definitive Biography of Lord Greystoke and Doc Savage: His Apocalyptic Life) that the Wold Cottage meteorite, which fell near Wold Newton, Yorkshire, England, on December 13, 1795, caused genetic mutations in the occupants of two passing coaches due to ionization. Many of their descendants were thus endowed with extremely high intelligence and strength, as well as an exceptional capacity and drive to perform good or, as the case may be, evil deeds. The progeny of these travellers are purported to have been the real-life originals of fictionalised characters, both heroic and villainous, over the last few hundred years, such as Sherlock Holmes, Tarzan, Doc Savage, and Lord Peter Wimsey.
Other popular characters included by Farmer as members of the Wold Newton family are Solomon Kane; Captain Blood; The Scarlet Pimpernel; Sherlock Holmes's nemesis Professor Moriarty; Phileas Fogg; The Time Traveller (main character of The Time Machine by H. G. Wells); Allan Quatermain; A. J. Raffles; Professor Challenger; Richard Hannay; Bulldog Drummond; the evil Fu Manchu and his adversary, Sir Denis Nayland Smith; G-8; The Shadow; Sam Spade; Doc Savage's cousin Patricia Savage and one of his five assistants, Monk Mayfair; The Spider; Nero Wolfe; Mr. Moto; The Avenger; Philip Marlowe; James Bond; Lew Archer; Travis McGee; Monsieur Lecoq; and Arsène Lupin.