 He wrote over 30 published books, including official biographies of HRH Prince Philip, Duke of Edinburgh ("The Duke – a Portrait of Prince Philip", 1991), Hodder & Stoughton), HRH The Princess Margaret ("Princess Margaret – a Life Unravelled" (2007), Orion Books) and cricket commentator Brian Johnston.Heald was also known for his mystery novels featuring Simon Bognor, special investigator, (10 titles), serialised by Thames TV, and more recently as creator of Dr Tudor Cornwall in a new crime trilogy published by Robert Hale Ltd