Welcome to the real horror show

It's Saturday night in Montreal and hundreds of film fans have arrived at Fantasia for the international premiere of The FP. A crazy, pumped-up retro comedy – think 8 Mile meets First Blood crossed with The Warriors – it's like nothing you've ever seen. But then so is the screening. Before curtain up, the crowd are whipped into a frenzy, as three natives are invited on stage to prove how patriotic they are; the first one to down a bottle of maple syrup wins. Needless to say, they all meet a sticky end. Welcome to the weird and wonderful world of genre festivals.

These are not the usual staid cinematic gatherings, where the movies are as polite as the patrons. "I think genre fans, in general, are more prone to emoting," explains Mitch Davis, co-director of Fantasia, which remains North America's biggest genre festival. "What's interesting about our crowd is that we can have 700 people in the room and it will sound like a rock concert. But at the same time, you won't hear people talk over dialogue. And you usually won't hear a mobile phone go off. There's a real respect for the film-making."

Compare this to Cannes, where each screening is peppered with executives talking on phones. "It's audience-driven," says Davis of Fantasia. "We never gear it to the industry." Partly it's because he started out as a fan. "The audience is the programmer, in a sense. The programmer was part of the audience. So there is that affinity as well. We try for there to be no barrier between fan and festival." Guests this year have included John Landis, the man behind An American Werewolf in London, and Britain's own Robin Hardy (director of The Wicker Man). Once upon a time, such gatherings dedicated to screening horror, science fiction or fantasy films were marginalised events. Not any more. The rise in genre festivals over the past few years has become palpable. Fantasia is now in its 15th year. This week, London will see the return of FrightFest, a five-day cinematic orgy that's been running for 12 years. And come September, Austin's Fantastic Fest – or the "Comic Con of film festivals" – will start its seventh edition. And that is just the bloodied tip of the iceberg.

In the UK alone, there's Grimm Up North (held in Manchester, in October), Abertoir (held in Aberystwyth in November) and the After Dark Horrorfest (key cities in March). Factor in long-standing events in Brussels, Sitges and Porto, not to mention young pretenders stretching from Morbido in Mexico to Neuchâtel in Switzerland and it's clear this lust for films that would've once been labelled "video nasties" is growing faster than fangs on a vampire. But why the sudden explosion?

"There was almost a frustration in the traditional film festival circuit, in that our types of movies, the ones that we love and champion, were somehow being relegated to B-movie status," suggests Tim League, Fantastic Fest organiser. League, who also programmes the midnight section of Austin's increasingly influential South By Southwest festival, points out that genre festivals don't simply have to consist of below-par slasher sequels. "I'm not a huge fan of the straight-ahead horror film. I like the horror films, which have more of a story to tell. So if it's just a straight-ahead slasher film, which we've all seen since the 1970s, we're probably not going to show it at Fantastic Fest. Adam Wingard, for example, made a movie called You're Next, which we're super-excited about playing. It's a horror movie but it's really exceptional storytelling."

Certainly, there's an argument to be said that these festivals are often in the vanguard when it comes to championing important film-makers. "The reason why we do well is that we get to know these people when they're just starting off," says FrightFest co-director Alan Jones. "If you look back at FrightFest, we were the first people to invite [The Dark Knight director] Christopher Nolan. He was one of our very first guests [with his no-budget debut Following]." Other friends of the festival include Pan's Labyrinth director Guillermo del Toro, who co-wrote/produced this year's opening film Don't Be Afraid of the Dark.

While the likes of Blair Witch Project and Paranormal Activity have been amongst the most profitable films of all time, Jones believes it still takes festivals like his to remind the industry of the commercial viability of genre fare.

Back at the creening of The FP, the audience roars its approval throughout, with one group to my right later accosting the co-director/star Jason Trost and telling him the film changed their lives.

It's a far cry from what Davis calls the "blaséness" that modern audiences, fed on a diet of Hollywood product, show.

"I feel our audience are ... really excited about the possibility of sharing in a group discovery."

FrightFest runs from 25 to 29 August (frightfest.co.uk)