Here's something you never hear people say: the Royal Family are really interesting. Really, really interesting. Popular belief has it that they're a brace of bland, right-wing toffs, who come as either (a) stroppy and ageing, in wellington boots, or (b) stroppy and younger, in nightclubs; and that it does not behove the thinking woman to spend more than six seconds a year thinking about them. And even those six seconds should be spent on saying: “Christ, how I yearn for revolution!” when looking at Prince Andrew and his gigantic, frying-pan-sized face - like JFK, inflated by a bicycle pump - being carted around the golf courses of Andalusia.

But you know what? The Royal Family are fascinating. Fascinating. If we like the kings and queens of the olden days - Elizabeth I, the doomed, permed Charleses, good old completely murderous Henry VIII and his overstuffed tights - then the modern lot are no less diverting. In Dorset, with his former mistress, the Prince of Wales is quietly building an organic toy village, in which he is some omnipotent, Duchy sausage-as- sacrament Godhead. Princesses Beatrice and Eugenie may sometimes socialise with controversial Camdenites - leading to the intriguing possibility that, one day, the Queen might be introduced to Amy Winehouse. And Diana - well Diana, as we all know, was murdered by aliens.

The Royal Family? They're a great bunch. As far as I recall, they cost us a penny a week - less than the TV licence - and they're up there with Holby City in terms of entertainment.

And, this week, ITV1 is widely in agreement with this sentiment - broadcasting a blockbusting two hours of documentary celebrating that capo di flat capo of the Mountbatten-Windsors - the Duke of Edinburgh.

At 87, his tenure in the public eye has spanned two very different media ages. At the beginning of his royal celebrity, the press were in the pockets of the Establishment. Prince Philip was, therefore, presented as “dashing” (in royal terms “dashing” means “has more than one eye, can stand up, knows the difference between up and down, won't have to be hidden away in a cellar in Glamis Castle for 60 years in the care of a drunkard maid”). Philip was depicted as “a mystery inside an enigma”.

Of course as the years have gone on, and the tabloid press has lost its reverence for the Royals, Philip has been further revealed to be, broadly speaking, “a mystery inside an enigma inside a git”, but I personally do not feel that dims his appeal. Well, perhaps “appeal” is too fond a word. And I've already used the word “fascination” twice. What I mean, I suppose, is that nearly everything about Prince Philip inspires an amused amazement.

Officially, he is the “first gentleman of the land” - even more senior in rank than Prince Charles, or the Prime Minister - but everything about him is so ... petty, and suburban. He was born in a house called Mon Repos on Corfu - I know! How Casa BevRon - seduced our beautiful future girl-Queen, like Tom Conti in Shirley Valentine, and then spent the next 60 years moaning, bitching, shooting, and making wholly inappropriate comments while on state visits.

“Do you still throw spears at each other?” to a group of Aboriginal businessmen.

In the foreword to a book: “If I'm reincarnated, I'd like to come back as a deadly virus, to counter overpopulation.”

And to the people of the Cayman Islands: “Aren't most of you descended from pirates?”

He is basically Alf Garnett with a wardrobe full of ceremonial swords. The people of Vanuatu Island, in the South Pacific, worship Prince Philip as a god, you know. They pray to pictures of him. Imagine if they ever saw an episode of Top Gear! It would blow their minds! They'd all convert over to the new God, Clarkson, like a shot.

Do not get me wrong. I am no smug contrarian. I do not think the world would be a “better place” if there were more “great characters” like Prince Philip. Broadly speaking, I think he's a total arse.

But if there were a single, doddery old diplodocus left in the world, you'd definitely want to put in some quality time observing its soon-to-be-extinct habits and mannerisms, before it finally keeled over. And for a two-hour chance to do just this, we must thank ITV1. We must thank them profoundly.

The Duke: a Portrait of Prince Philip, Mon & Tues, ITV1, 9pm

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