David Craig Owen Thomas (born 24 November 1942) is a Welsh author of thrillers, notably the "Mitchell Gant" series.
He was educated at Cardiff High School and University College, Cardiff, obtaining his M.A. in 1967. He became an English Teacher, and was Head of English at the Shire Oak School, Brownhills, West Midlands. His best-known novel, Firefox (1977) became a successful Hollywood film. Other books include Snow Falcon and A Different War. Although the invention of the techno-thriller genre is often attributed to the better-known Tom Clancy, many feel that Thomas was its true originator.
Most of Thomas's novels are set within MI.6 and feature the characters of Sir Kenneth Aubrey and Patrick Hyde.