It has been a mystery that would have baffled Perry Mason or Ellery Queen. Since Meghan Markle and Prince Harry informed a shocked Oprah Winfrey in their bombshell interview that “there were concerns and conversations” about “how dark” the skin color of their first child-to-be was likely to be, the couple have slowly dripped information into the public domain.

It’s been made clear that it was a “senior royal” who expressed the opinion, albeit neither the Queen nor the Duke of Edinburgh. Although given the latter’s public remarks on race and nationality, it might have been easiest if the soon-to-be-late Prince Philip had simply claimed responsibility.

Now, the “senior royal” has finally been fingered, and the alleged guilty party is Prince Charles. A new biography of the younger royals, Brothers and Wives: Inside the Private Lives of William, Kate, Harry and Meghan, by the royal correspondent Christopher Andersen, has suggested that a conversation took place between Charles and Camilla on the day of Prince Harry’s engagement in November 2017 in which the King-to-be said, “I wonder what the children [of Harry and Meghan] will look like.” When Camilla responded, “Absolutely gorgeous, I’m certain,” Charles is alleged to have lowered his voice and mused, “I mean, I wonder what their children’s complexion might be?”

Andersen himself has suggested that the comment was not racist per se — “the innocent musings of a grandfather” — perhaps with the implication that the now 73-year old Prince is insufficiently au fait with the workings of the modern world to understand that such an off-color [sic] remark might cause deep offense if it was to be repeated. Or, indeed, alluded to on national television.

Instead, Andersen places the blame at the doors of “scheming courtiers” who “spun” the story into something more incendiary than it actually was, even if Prince Harry was said to have “angrily confronted” his father, who replied that his son was being “overly sensitive about the matter.” But nonetheless, the reputational damage has been done.

Initially, Clarence House simply offered a curt statement that “this is fiction and not worth further comment,” but as there are suggestions that Charles has consulted his lawyers, the story has acquired its own momentum. If legal action was launched against Andersen and his publisher Simon & Schuster, it would lead to an embarrassing court case in which various revelations within the book — such as Charles and Harry not having communicated since Prince Philip’s funeral, and William and Harry no longer speaking on the telephone — would be aired publicly once again. Various members of royal staff, past and present, could be called to testify as to the veracity, or otherwise, of the claims.

The controversy comes at an unfortunate time for “the Firm,” where Barbados’ recent decision to become a republic has led to whisperings about whether such a thing might be possible elsewhere. Prince Charles was on hand at the ceremony in Bridgetown to make a solemn speech, in which he acknowledged “the darkest days of our past and the appalling atrocity of slavery, which forever stains our history.” He then praised the Barbadian people for forging their path with “extraordinary fortitude,” though it was unfortunate that the man delivering these sentiments has himself been implicitly accused of racism.

I doubt there will be a definitive answer to the question of who the “senior Royal” was, unless Harry and Meghan break their silence for another high-profile televised interview. Stranger things, after all, have happened. But the slow drip-feed of innuendo and briefings and counter-briefings and outraged public statements continues to damage the Royal Family at an existential level. Even as the world delightedly awaits each new titbit of news and gossip, the metaphorical ravens seem about to leave the Tower of London. And once they’re gone, it’s anyone’s guess what happens next.