The wobbly titles – “by kind permission of the Marquess of Abergavenny” –  might make it seem impossibly quaint at first, and some elements are truly bizarre, like the bloomers hung up like a ghost on a black background and Benny Hill being dressed up in a toga. But it’s “Devised, Written and Spoken by” the fantastically elegant Doris Langley Moore, who actually packs the whole thing full of facts and intelligent opinions, so you have to concentrate to keep up with her points about male facial hair, female back decolletage and other aspects of body shape and dress through the ages. Brilliantly, the BBC have put the whole series in their archive. They’ve also got some great accompanying documents, including a grumbling audience report showing that people in the Fifties didn’t know how lucky they were.

Now please can someone make a decent new programme about fashion: give us a rest from Twiggy and get someone like Diane Pernet in, to tell us something we don’t know.

At first this seems just an entertaining throwback to those portmanteau films that stuck a few ghost tales together, added some kind of sinister, squinting narrator and hoped for the best – but the modern story that links everything together here turns out to be properly terrifying.

Can’t say much more without spoiling it – just watch it quick, and don’t answer that knock at the door…