Dennis Yates Wheatley (8th January 1897 - 10th November 1977) was a British writer whose prolific output of thrillers and occult novels made him one of the world's best-selling authors from the 1930s through to the 1960s. His first book, Three Inquisitive People, was not published when completed, but came out later, in 1940. However, his next novel made quite a splash. Called The Forbidden Territory, it was an immediate success when issued by Hutchinson in 1933, being reprinted seven times in seven weeks. After finishing The Fabulous Valley, Wheatley decided to use the theme of black magic for his next book. He wrote: "The fact that I had read extensively about ancient religions gave me some useful background, but I required up-to-date information about occult circles in this country. My friend, Tom Driberg, who then lived in a mews flat just behind us in Queen's Gate, proved most helpful. He introduced me to Aleister Crowley, the Reverend Montague Summers and Rollo Ahmed. The release the next year of his occult story, The Devil Rides Out—hailed by James Hilton as "the best thing of its kind since Dracula"—cemented his reputation as "The Prince of Thriller Writers."
Wheatley mainly wrote adventure novels, with many books in a series of linked works. Background themes included the French Revolution (the Roger Brook series), Satanism (the Duke de Richleau series), World War II (the Gregory Sallust series) and espionage (the Julian Day novels). Over time, each of his major series would include at least one book pitting the hero against some manifestation of the supernatural—making them into fantasy and specifically contemporary fantasy. He came to be considered an authority on Satanism, the practice of exorcism, and black magic, toward all of which he expressed hostility. During his study of the paranormal, though, he joined the Ghost Club.
In many of his works, Wheatley wove in interactions between his characters and actual historical events and individuals. For example, in the Roger Brook series the main character involves himself with Napoleon and Joséphine whilst spying for Prime Minister William Pitt the Younger. Similarly, in the Gregory Sallust series, Sallust shares an evening meal with Hermann Göring. In "They Used Dark Forces", the penultimate book of the Sallust series, Göring gets a surprisingly positive depiction as an honourable man who disliked the systematic killing of the Jews (though not actually doing anything to stop it) and who wanted to end the war when realizing that Germany was doomed to lose it; Göring is contrasted with Goebbels, who according to Wheatley "was on the extreme left" and "took seriously the Socialist part of National Socialism".
During the 1930s, Wheatley conceived a series of mysteries, presented as case files, including testimonies, letters, and pieces of evidence such as hairs or pills. The reader had to inspect this evidence to solve the mystery before unsealing the last pages of the file, which gave the answer. Four of these 'Crime Dossiers' were published: Murder Off Miami, Who Killed Robert Prentice?, The Malinsay Massacre, and Herewith The Clues!.
Wheatley also devised a number of board games including Invasion (1938), Blockade (1939) and Alibi (April 1953).
In the 1960s, Hutchinson was selling a million copies of his books per year, and most of his titles were kept available in hardcover. A few of his books were made into films by Hammer, of which the best known is The Devil Rides Out (book 1934, film 1968). Wheatley also wrote non-fiction works, including an account of the Russian Revolution, a life of King Charles II of England, and several autobiographical volumes.
He edited several collections of short stories, and from 1974 to 1977 he supervised a series of 45 paperback reprints for the British publisher Sphere with the heading "The Dennis Wheatley Library of the Occult", selecting the titles and writing short introductions for each book. These included both occult-themed novels by the likes of Bram Stoker and Aleister Crowley (with whom he once shared a lunch) and non-fiction works on magic, occultism, and divination by authors such as the Theosophist H. P. Blavatsky, the historian Maurice Magre, the magician Isaac Bonewits, and the palm-reader Cheiro.
Two weeks before his death in November 1977, Wheatley received conditional absolution from his old friend Cyril 'Bobby' Eastaugh, the Bishop of Peterborough. He was cremated at Tooting and his ashes interred at the South Cemetery section of Brookwood Cemetery, under a tall tree near the entrance. He is also commemorated on the Baker/Yates family monument at West Norwood Cemetery.
His estate library was sold in a catalogue sale by Basil Blackwell's in 1979. It suggested a well-read individual with wide-ranging interests, particularly with respect to historical fiction and Europe.
His grandson Dominic Wheatley became one of the co-founders of the software house Domark, which published a number of titles in the 1980s and 1990s