art panel in 2018 Campbell wrote special radio
pantomimes for the
BBC in 1982 and 1983, entitled
Dick Whittington and
Sleeping Beauty. She is best known for her books on
Diana, Princess of Wales, and
Queen Elizabeth the Queen Mother. Her 1992 book,
Diana in Private: The Princess Nobody Knows, provided information about Diana's struggle with
bulimia and her affair with
James Hewitt (insights into these matters deriving from the fact that "one of [Campbell's] closest friends was one of [Diana's] closest friends"). Campbell was dismissed as a fantasist, but some of her claims were later vindicated.
Diana in Private appeared on
The New York Times Best Seller list in 1992. Campbell later said the book initially started as an authorised official biography but later Diana decided to make it an unofficial one and use it as a "get out of jail card" after being "advised by friends that she should play the victim." Her 1993 book,
The Royal Marriages, was criticised by
Lynn Barber for lack of verification for her assertions. Barber described her pleasure in encountering "an author so exhilaratingly untrammelled by any fear (or knowledge?) of the libel laws. Nothing is beyond her", concluding "either [Campbell] is the greatest gossip since
Pepys or she is a complete fabulist: one can only read it and gawp ... Lady Colin Campbell never bothers her head with anything so tedious as verification". Campbell's 2012 book,
The Untold Life of Queen Elizabeth The Queen Mother, was met with criticism. Her theorising, including claims quoting the
Duke of Windsor regarding the Queen Mother's parentage, was dismissed by writers
Hugo Vickers and Michael Thornton as "bizarre" and "complete nonsense". The timing of the publication of Campbell's book, a service of remembrance for the Queen Mother marking the tenth anniversary of her death, was also condemned. In
The Sunday Times, the journalist Lynn Barber opined that Campbell's claims ought not to be dismissed out of hand. In some subsequent interviews, Campbell put some distance between herself and a few of the theories first articulated in her book, including during a filmed conversation in a 2016 documentary with historian
John Julius Norwich, who knew the Queen Mother when she was alive and challenged some of Lady Colin Campbell's claims. In 2020, Campbell released another biography called
Meghan and Harry: The Real Story, addressing
Meghan and
Prince Harry's life, romance and ensuing rift with the royal family. Julie Miller in
Vanity Fair described the book as "aristocratic gossip", and labelled it as deeply subjective. Her other books include a book about her own mother titled ''Daughter of a Narcissus: A Family's Struggle to Survive their Mother's Narcissistic Personality Disorder
, and a book about Queen Elizabeth II titled The Queen's Marriage
. Campbell has been called a "polarizing figure" by Vanity Fair'' and an "amusing dinner partner" by
Tina Brown. ==Television==