Joan Alice Cowdroy was born in London in 1884, the third child of Arthur Rathbone Cowdroy and Marie Grace Aiton.

The author wrote a series of well-received romantic novels in the 1920’s, but her career in crime fiction did not begin until 1930 with the publication of The Mystery of Sett which introduced one of her series detectives, Chief-Inspector Gorham. Her Asian detective, Mr. Moh, made his first appearance a year later and became a long-standing recurring sleuth in the author’s crime fiction.

Joan A. Cowdroy, a life-long spinster, died in Sussex in 1946.