Once upon a time there was a movie with an $85 million budget. It featured princes and princesses and took millions at the box office. The directors and producers of Hollywood rubbed their hands with glee; they'd found the magic potion that would help them turn simple stories into untold riches.

Fairy tales are big business in 2012. The $85 million budget was for Mirror Mirror: The Untold Adventures of Snow White; just one of the films cashing in on the current trend for fairytales. It will be followed by the darker, reportedly more kick-ass version, Snow White and the Huntsman starring tweenage idol Kristen Stewart, due for release in June this year.

Fairy tales are the film genre du jour this year, and it's a trend that is set to continue. In the next two years, up to twenty fairy tale films are in production or due for release, with budgets big enough to make a giant choke on his 'fi-fie-fo-fum'. Those confirmed include Jack the Giant Killer starring Nicholas Hoult (About a Boy); Hansel and Gretel: Witch Hunters, starring Gemma Arterton (Quantum of Solace) and Maleficent starring Angelina Jolie. Guillermo del Toro is rumoured to be circling a new take on Beauty and the Beast with Emma 'Hermione' Watson, and has just announced his involvement in Pinocchio - a story Tim Burton's also allegedly had his eye on, with Robert Downey Jr in mind to play Gepetto. In addition to all that, Atonement director Joe Wright is said to be considering a retelling of The Little Mermaid.

But not everyone is keen to jump on the pumpkin carriage; speaking to press at comic and film convention WonderCon, Wright said he'd rather wait for the 'onslaught of fairy tale adaptations' to subside before starting The Little Mermaid. But with more new releases than there are mice in Cinderella's kitchen, it seems that fairy tales won't be disappearing anytime soon. So just how, and why, have these stories from childhood come to have such appeal to a modern, film-going audience?

The audience, in fact, is a key factor in the quest to finding these films' success. Dr. Sarah Dunnigan, a senior lecturer in English and Scottish Literature at the University of Edinburgh, teaches the honours year Fairy Tales course. She suggests that the rise in popularity of fantasy films has revealed a pre-existing appetite for the fairy tale genre.

'Last year's Red Riding Hood was very much trying to appeal to the Twilight generation,' she says. 'The visual aspects and the focus on beauty, death, desire and horror seem moulded to that audience.'

There's also the fact that everyone knows about Cinderella, Sleeping Beauty and Snow White. Filmmakers have a ready-made store of narratives that the public know and will be willing to pay good money to see done in a different way. Tales from the Brothers Grimm and Hans Christian Andersen are familiar to children across the globe, but film can offer different perspectives and famous faces.

Maleficent, due for release in 2014, retells Sleeping Beauty from the view of the Evil Stepmother (Jolie) and is another film making the jump from Disney animation to live-action movie. But have Disney's iconic animated films meant that modern movies only scratch the surface of the original tales? Those by the Grimms and Andersen are more horror than fantasy; in the original Cinderella, her stepsisters hack off bits of their feet to fit into the glass slipper. But it's doubtful that modern filmmakers will embrace this genre; self-mutilation for a man, no matter how hot the Prince, is not blockbuster material. New versions instead seem to still pander to sugar coated Disney movies, preferring magic and mayhem to blood and gore.

Never has a happy ever after been more unwelcome. Dunnigan suggests however that rebellious filmmakers will create more successful re-imaginings of fairy tales. 'Burton and del Toro would be brilliant in representing the subversive nature of fairy tales', she says. 'These are troubling and dark stories, but some modern films are not responding to this darkness in the way that Pan's Labyrinth did, using the fairytale to talk about abuses of power and political corruption. Most modern versions seem to focus on the surface value.'

The big question is whether this trend will go to the ball, or disappear at midnight. 'I'd like to think it will endure', muses Dunnigan, 'but knowing popular culture it might not. People may think they've seen enough versions of Snow White, but they won't ever go away completely; they'll be re-invented in a different form. My fear is that it will eventually dampen the delight we take in these tales.'

Mirror Mirror Trailer