Joan Fleming was born Joan Margaret Gibson, the daughter of David and Sarah Elizabeth (née Suttcliffe) Gibson. She was born in Horwich, Lancashire, England, on March 27, 1908. Her education was at Brighthelmston School, Southport, Lancashire, and in Switzerland at Grand Belle Vue, Lausanne, and Lausanne University. She worked in London as a secretary to a doctor from 1928 to 1932, when she married Norman Bell Beattie Fleming. They had three daughters and a son. Her husband died in 1968.
Fleming wrote more than thirty novels that are classified as mysteries (some are historical mysteries), at least five works of juvenile fiction, and a nonfictional volume concerning William Shakespeare. In 1962, she received the Gold Dagger Award given by the Crime Writers’ Association for that year’s best mystery publication, When I Grow Rich. She won the award again in 1970 for her novel published that year, Young Man, I Think You’re Dying. Fleming died on November 15, 1980.