This week I have been working with the great Dame Judi Dench. We have been rehearsing a song by Noël Coward for a show we are doing together at the Royal Albert Hall next Friday. Judi met Sir Noël not long before he died in 1973. What she remembers best is his amused smile and the strong scent of the fragrance he wore. Whenever I think of him, I recall his wise advice to anyone confronted with unfair criticism: ‘Rise above it.’ I hope that is what the King is going to do in the face of the bewildering brouhaha that has come with the publication of Omid Scobie’s book Endgame. Charles is not a racist. Not remotely. Anyone who has spent any time with him over any number of years will tell you that. I don’t know if Scobie-Doo has met him. In fact, I am not sure who he has met. As a fellow royal biographer, I have encountered quite a few senior royals and their staff and none that I know seems to have met Scobie either. Where is he getting his material from and why is the press giving it quite so much attention? From what I have read of Endgame, it feels a bit like the more recent episodes of The Crown: smoothly done, but full of wild surmise, hearsay and hunches.

One of the book’s least convincing assertions is that the Prince of Wales is impatient to be king. There is no evidence for that – and, given the impressive longevity of Charles III’s parents, no prospect of it soon either. I get the impression that our 75-year-old sovereign is just hitting his stride and quietly bubbling with ideas and plans that will keep him busy well into his nineties.

All my role models are of riper years. Never mind Dame Judi, who moves into her 90th year this Saturday; last week I recorded my Rosebud podcast with Dame Sheila Hancock, already 90 and full of fire, fury and funny stories. After two hours of brilliant banter, she concluded our conversation with a happy cry of ‘nothing matters a damn’ and set off for her Pilates class. This week I had lunch with Patricia Owtram, 100, a former second world war Wren and military intelligence decoder, the founding producer of University Challenge, and now, as she told me proudly: ‘The only centenarian in Chiswick trained to use a Sten gun.’

As you can tell, I am not averse to a bit of name-dropping. I like to feel I have come face to face with most of the notable names of our time. David Nixon (TV magician when I was a boy), Marni Nixon (who sang the songs for Audrey Hepburn in My Fair Lady), Richard Nixon (37th President of the USA) – I’ve met them all. So imagine my excitement when, a few years ago at a gala dinner at the Banqueting House in Whitehall, I found myself rubbing shoulders with Dr Henry Kissinger. The occasion was a grand fundraiser for the Edward Heath Charitable Foundation and the high point of the evening was Dr Kissinger being interviewed on world affairs by Sir John Major. The British establishment had turned out in force. Sir John asked his first question – about relations between China and the West, as I recall. Dr Kissinger growled his reply. It was not brief, but it was incomprehensible. The combination of his thick German accent and his guttural, gravelly voice meant that we could hear him rumbling, but we couldn’t follow a word he said. After 40 minutes of this torture, Sir John thanked our distinguished guest, and, being British and well brought-up, we gave him a standing ovation.

Is it possible to enjoy a merry Christmas in the war-torn world we are living in right now? I think so. Not long after the Japanese attack on Pearl Harbor on 7 December 1941, Winston Churchill travelled to Washington DC with his chiefs of staff to meet President Roosevelt. On Christmas Eve, from the White House, Winston Churchill gave a broadcast to the world that I am surprised is not better known. He gave his listeners permission to briefly cast aside ‘the cares and dangers which beset us’ and let each home ‘be a brightly lighted island of happiness and peace’ in a world of storms. ‘Let the children have their night of fun and laughter. Let the gifts of Father Christmas delight their play.’ Do Google the speech and read it aloud to your family this Christmas Eve. It’s stirring stuff.