The Secret Royals: Spying and the Crown, from Victoria to Diana by Richard J. Aldrich and Rory Cormac
Princess Diana summoned a butler one day to help to shift furniture in her sitting room at Kensington Palace. They rolled up the carpets and underlay and took up the floorboards.
Diana was searching for hidden microphones, but found nothing. “She worried about devices being placed in plug sockets, light switches or lamps,” Paul Burrell, the butler in question, later revealed. She was so convinced that “dark forces” were watching her that she even took down a mirror, after being told that conversation could bounce off the glass and be monitored outside.
