Have you ever seen the Magic Roundabout film Dougal and the Blue Cat? Look it up on YouTube. It’s all about a blue cat, wandering around in the magic garden, trying to turn everything blue. It’s pretty weird. Also check out that clip of Rainbow, which is full of puns about “playing with your twanger” and “Jane’s lovely pair of maracas”. They weren’t all like that, were they? And those Thundercatsouttakes are pretty funny. And did you remember how trippy Button Moon was? And Bagpussreally was a creeping nightmare, wasn’t it? And, God, remember Camberwick Green? Did we ever realise how much Windy Miller looked like Arthur Scargill? And – whoosh! – there goes the day. I was supposed to be investigating what makes a children’s TV programme a “cult classic” (as opposed to merely something fondly remembered) but it isn’t easy.

I keep getting distracted and watching stuff. My main discovery is that there doesn’t appear to have been any serious psychological or sociological research into the phenomenon. Ever. I imagine academics set out down that route, and then waste their funding and tenure watching Roobarb & Custard.

In his Encyclopaedia of Cult Children’s TV (Allison & Busby), Richard Lewis has a bold stab at a definition. He reckons that family programmes (The A-Team, Knight Rider etc) don’t count, and nor do sitcoms and school programmes. I concur with the first two, but I also have unsettling memories of the latter. (Was there once something about blond alien twins teaching maths?) Lewis also jettisons “programmes that were obviously the work of Satan”, such as The Keith Harris Show. This is fair. (See also Witzbit, Wacaday, anything with Grotbags in it.) I think Lewis is close, but not quite there. He defines what cult children’s TV isn’t. An extra dimension is needed: something to do with weirdness or subversion.

Although weirdness alone is not enough. After some consultation, the weirdest example of children’s TV brought to my attention is a cartoon from the 1990s entitled Captain Planet Saves Belfast. Google it, and watch the hero convince an oddly accented assortment of Protestants and Catholics not to detonate a nuclear bomb but to open an interfaith bakery instead. Weird, yes. Cult, no.

Certainly, a subversive element helps, even if the most celebrated subversive bits of children’s television invariably turn out to be hoaxes. That Rainbow episode (above) was some sort of in-house joke and never broadcast. And John Ryan has successfully sued newspapers for repeating the myth that Master Bates, Seaman Staines and Roger the Cabin Boy appeared in his Captain Pugwash. As for The Magic Roundabout, there is doubtless a wholesome reason as to why Dougal should have gone all peculiar whenever a hippy rabbit called Dylan gave him a sugar lump.

It seems to be entirely arbitrary that some children’s TV classics are decreed to be “all about drugs” while others are not. Yes, Mr Benn did appear to live a very active inner life. Indeed, Scooby Doo’s Shaggy was a hippy who was always hungry, lived in his car, and talked to his dog.

Children’s fiction has always been surreal, back to the Brothers Grimm and beyond. Remember, Pink Floyd went nuts over Alice in Wonderland and The Wizard of Oz. No surprise, then, that a generation later, acid-house culture did the same with television. Probably most of what we class as “cult” children’s TV was the childhood viewing of the rave generation in the late 1970s and early 1980s. When the Prodigy sampled those peculiar stranger/danger advertisements in Charly (1991), they unleashed a trend. Soon afterwards, Shaft had Roobarb & Custard, Urban Hype had A Trip to Trumpton and (this was when it started to get tiresome) Smart E’s had Sesame’s Treet.

In his book Generation Ecstasy, Simon Reynolds describes all this as “nostalgic infantilism”. Children’s TV provides a shared mythology. When I was a student, a decade ago, there was a joke that, sooner or later, everybody ended up having the children’s TV conversation. Take any group of adults of a similar age, and it may be all they have in common. This is the kind of thing into which all those later examples of cult children’s TV (Balamory, Teletubbies, Tweenies) are desperate to tap. Because kids aren’t fussy. Kids will watch anything. Kids don’t buy the merchandise, and they don’t buy the DVDs. Success lies in snaring nostalgic grown-ups and letting them think they are giving their kids something to talk about 12 years later, while making friends and getting slightly pissed on cider.

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