Ruby Mildred Ayres was born on 28 January 1881 in Watford, Hertfordshire, the third daughter of the marriege formed by Alice (née Whitford) and Charles Pryor Ayres, a London-based architect. In 1909 she married Reginald William Pocock, a insurance broker, and they lived in Harrow until his death in a train accident. As widow without childrens, she moved to her sister's home at Weybridge, Surrey.
She started to write as a girl, and her first story was published in a magazine shortly after her marriage, and in 1912 she published her first novel, Castles in Spain. In September 1915, with her first popular success, Richard Chatterton, V.C. (which sold over 50,000 copies in the first three years), she moved publishing houses to Hodder and Stoughton, where she remained until her death in 1955. She wrote over 150 novels and serialised works. Several of her works became films and she did screenwriting for Society for Sale among others. She corresponded with Douglas Sladen, and also was was possibly an inspiration for the P. G. Wodehouse character Rosie M. Banks. She died on 14 November 1955 in a nursing home in Weybridge, aged 74, of a combination of pneumonia and a cerebral thrombosis. She was cremated four days later at Golders Green in north London.