A couple of weeks later, Michael Fagan overcame the supposedly foolproof security system of Buckingham Palace and broke into the Queen’s bedroom on 9 July. By unfortunate coincidence, all the Queen’s family were out of London and her page, Paul Whybrew, was taking the corgis for their morning walk. The Queen’s first reaction on waking and seeing a man at the foot of her bed was that it must be member of staff and she told them to get out. Fagan has told many versions of the story, but suffice to say the Queen bravely kept him talking while she tried to summon security with the panic button – but there was no response. Eventually her housemaid appeared and screamed with shock when she saw the intruder. The Queen, still in her nightdress, managed to lure Fagan out of her bedroom and into the pages’ pantry, where her maid gave him a cigarette.

When Whybrew returned with the dogs, she signalled to him to go into the pantry, which he duly did, plying Fagan with whisky until security arrived. The Queen claims she was not unnerved as it was so surreal she didn’t have time to be frightened. But she must have been rattled that such a thing could happen, although she has dined out on the story and imitated her maid’s horrified reaction ever since.

What was particularly alarming was that someone could scale a wall of the palace, get through an open window, walk along a couple of corridors and enter the Queen’s bedroom undetected. Prince Philip, who had been sleeping in the adjoining bedroom, had left the palace early and was furious when the story broke that the entire world should know their sleeping arrangements. He was, of course, incandescent with rage that such a thing should be allowed to happen and applauded the bravery of his wife in remaining calm and collected in the face of the intruder.

A week later, the Queen went to hospital, ostensibly to have a wisdom tooth removed, but conveniently at the same time as her long-serving police officer Commander Michael Trestrail, of whom she had been very fond, had to resign after it was revealed he was conducting an affair with a male prostitute.