Donald Serrell Thomas (18 July 1934 – 20 January 2022) was a British crime writer. His work primarily included Victorian-era historical, crime and detective fiction, as well as books on factual crime and criminals, in particular several academic books on the history of crime in London. He wrote a number of biographies, two volumes of poetry, and also edited volumes of poetry by John Dryden and the Pre-Raphaelites.