As Prince William's former Private Secretary Simon Case announces he is stepping down as Cabinet Secretary, could ‘the keeper of secrets’ pen a bombshell book about Prince Harry and Meghan Markle?

As Cabinet Secretary, Simon Case is considered by many to be the most powerful man in Whitehall – and as a private secretary to Prince William, he had access all areas to the royal feud of the decade – might he follow in Prince Harry's footsteps and tell all?