On the covers are the most innocent of titles: Grimm’s Fairy Tales in their English version or Children’s and Household Tales in the original German editions published two hundred years ago. Nice tales for nice children.

But behind the safe titles lie dark stories of sex and violence – tales of murder, mutilation, cannibalism, infanticide and incest, as one academic puts it. They are far from anything we might imagine as acceptable today. If they were a video game, there would be calls to ban them.

Jacob and Wilhelm Grimm were writing in a different world. They lived in the town of Kassel in Germany and studied law and language as well as writing more than 150 stories which they published in two volumes between 1812 and 1814.

Some stories have fallen out of favour but some – Red Riding Hood, Cinderella, Hansel and Gretel, Snow White – seem eternal. They have morphed into countless adaptations; Disney disneyfied them and new filmmakers and novelists continue to rework them. Comics from Japanese Manga to the erotic and ‘adult’ depict the characters of the Grimm brothers’ tales.

But even in their original, they are far from saccharine, according to Maria Tatar, professor of Germanic folklore and mythology at Harvard University: “These tales are not politically correct. They are full of sex and violence. In Snow White, the stepmother asks for the lungs and liver of the little girl. She's just seven years old and she's been taken into the woods by the huntsman. That’s pretty scary.

“And then the evil stepmother is made to dance to death in red-hot iron shoes. In Cinderella, you’ve got the stepsisters whose heels and toes are cut off.”

Adult themes

These tales of gore and sexuality – John Updike called them the pornography of an earlier age – are still going strong. “I can't even keep track of the number of new versions of Snow White,” says Professor Tatar. “And these aren't just Disney productions – you have film-makers making very adult versions of the fairy tales, drawing out the perverse sexuality of some of these tales.”

They are tales of right and wrong. There are clear morals to be drawn – deception and dishonesty are punished; honest hard work is rewarded; promises must be honoured; beware of strangers – and especially the forest.

But that can’t be the enduring appeal. Moralistic lectures never entertained anyone – but gory tales of suspense are a different thing. They do have an eternal following. As Professor Tatar puts it: “They give us these ‘what if’ scenarios – what if the most terrible thing that I can imagine happened? – but they give us these scenarios in the safe space of ‘once upon a time’. I'm going to tell you the story and I'm going to show you how this hero or this heroine manages to come out of it alive.” And not just alive, but also ‘happily ever after’.

It’s clear that many children love the gory bits. And it’s clear that many parents don’t. A survey last year found that many reported that their children had been left in tears by the gruesome fate of Little Red Riding Hood. Some parents wouldn’t read Rumpelstiltskin to their children because it was about kidnapping and execution. And many parents felt that Cinderella was a bad role model for daughters because she did housework all day.

Some pop culture versions of the tales have sugar-coated their more unpalatable aspects. It’s true that the Cinderella made by Disney in 1950 is a work of schlock – the titles of the songs (A Dream is a Wish Your Heart Makes”, Bibbidi-Bobbidi-Boo and Sing Sweet Nightingale) give the flavour. But Disney’s older animated versions of Grimm Fairy Tales are much darker.

“In Snow White which was made in 1937,” says Professor Tatar, “the Wicked Queen goes down into the basement where she's got a chemistry set which she's going to use to turn the apple into a poisoned apple. There are ravens down there and skulls and mysterious dusty tomes.

“And then she transforms herself into an old hag. She goes from the fairest of all to the ugliest of all.

“I think that's really an adult moment which enacts our anxieties about aging. First, her voice changes and then her hands begin to change and there she is a decrepit old woman.

“I think Disney picked up on the scariness of fairy tales as something which appeals to both children and adults”.

Evil thoughts

You get a flavour of these debates and nuances in the town of Kassel in Germany at the moment. It’s where the two brothers grew up and lived (in the same house, Wilhelm married to Henriette; Jacob single until his death).

There have been productions of some of the tales in the Botanical Gardens and a thought-provoking exhibition in the city’s documenta-Halle. It displays the original publications of the tales and the dictionaries and other works produced by the brothers.

But the most interesting exhibits are the ones designed to make people think. There are videos of glossy perfume adverts featuring a radiant Little Red Riding Hood taming the wolf with her fragrance. There is a section marked “No Access for Minors?” where, behind a thick curtain, you can read the most violent extracts from the tales through slits in the wall.

One of the curators, Louisa Dench, said these extracts show that good triumphs over evil and that the bad get punished. There are clear choices. “There is good and there is bad and you know what’s good and what’s bad and there’s no question about it. And that’s very understandable for children. It’s very clear, and good always wins. That’s important”.

She thinks the secret of the enduring appeal is that much is left to the imagination. “You have only limited characterisation so there’s a lot you can imagine yourself,” she says. “If someone reads them to you, your mind can build up its own picture. That’s part of the magic”.

It is a magic based on fantasy and that may be what protects the tales from the unmitigated wrath of parents. Children – some children – do seem to like the darkness of horror but, perhaps, not if it becomes too realistic. Some parents feel uneasy about tales for children where a child's hands are cut off (The Girl without Hands) or where a man is pushed down stairs (The Story of the Youth Who Went Forth to Learn What Fear Was) – but children know it is fantasy.

Their fantastical darkness may have protected today's video games from the wrath of tougher laws. Two years ago, the Supreme Court of the United States struck down a lower court's ruling that video games should be banned. Justice Scalia ruled that depictions of violence had never been regulated. “Grimm’s Fairy Tales, for example, are grim indeed,” he wrote, referring to the gory plots of Snow White, Cinderella and Hansel and Gretel.

Grim, indeed. And exciting, too, to generations of children and adults for two hundred years – and perhaps for another two hundred.

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