She began working for the War Office in 1940 before the family moved temporarily to the United States. She began writing while working for the British Purchasing Commission in New York City during World War II. Her first book was "The Magic Bed Knob; or, How to Become a Witch in Ten Easy Lessons", published by J. M. Dent in 1945. Its sequel "Bonfires and Broomsticks" followed two years later and they were re-issued jointly as "Bed-Knobs and Broomsticks" in 1957. The stories became the basis for the 1971 Disney film "Bedknobs and Broomsticks".