Painter, stage-set and costume designer, writer and noted horsewoman, born in Kilcreggan, Dunbartonshire, the sister of Anna Zinkeisen. She studied at Harrow School of Art and won a scholarship to the Royal Academy Schools. Her first painting was shown at the RA in 1918, a portrait of Anna, done when Doris was only 16. She was employed by the impresario Nigel Playfair, which led to a lifelong association with the theatre. She worked with C.B. Cochran, and painted the portraits of many celebrities, such as Anna Neagle and Evelyn Laye. She also worked at the Old Vic with Laurence Olivier creating his make-up for the film Richard III. She collaborated with Noel Coward on many of his early stage plays and wrote a key book, Designing for the Stage. She painted murals for the Verandah Grill on the liner Queen Mary and won bronze, silver and gold medals at the Paris Salon. At the end of World War II she was the first artist to enter Belsen concentration camp; two of her paintings of Belsen are in the Imperial War Museum. She was a fine horsewoman, winning the Moscow Cup for the Supreme Hack Championship at the International Horse Show in 1934. Her twin daughters were the artists Anne and Janet Grahame Johnstone.
Her pre-war work is characterised by a strong sense of design, often in a Surrealist vein, with hard edges and rich, vibrant colour. After World War II her work became increasingly formulaic, taking as its subjects ballet scenes and relaxed carriage rides through parks. Remarkably, she continued producing these until the end of her life, despite suffering from Alzheimer's for the last ten years.