FrightFest is back and this year it's the unlucky for some 13th edition of London's annual 'Woodstock of gore' (copyright Guillermo Del Toro). The five-day bonanza of blood, guts and scares was created in 2000 by producer Paul McEvoy, journalist and broadcaster Alan Jones and distributor/booker Ian Rattray. During that time it has outgrown the Prince Charles Cinema (2000-2004) and Odeon West End (2005-2008) to finally settle down, for the time being, at the Empire in Leicester Square.

A record 48 films and the addition of a third screen make 2012's FrightFest the biggest in its history. Eleven countries are represented, with perhaps the most obscure entry coming from Chile. Based on a true story, Patricio Valladares' Hidden In The Woods is about two sisters raised in isolation and tormented by a drug-dealing dad.

"A Chilean movie that no one has ever heard about is going to get the biggest reaction on a big screen in the heart of the West End," says Alan Jones. "It's good that we provide that outlet. I think this is what we're here for."

FrightFest is also here for the fans. The growth of the event has not made the tickets any less precious. When the five-day weekend pass tickets go on sale in early July what has been affectionately nicknamed the 'sleepy queue' forms. A core of FrightFesters spend a night under the stars and bemused glare of drunken revellers in Leicester Square until 7am, when the rest of their horror brethren begin to join them. The Empire's doors open at 11am and online sales usually begin 90 minutes later. Alan, Ian and Paul are all in attendance to keep spirits up. A white suited Tom Six, of The Human Centipede fame, even lent a hand this year.

"I laughingly said to someone in the queue don't worry. Now you're here you'll be fine," recalls Alan. They were, but only just. "It was the first time we've sold out [weekend passes] so fast."

Proceedings kick off with one of the twelve UK productions that are premiering. The Seasoning House takes place in a Balkan establishment where young girls are prostituted to the military. The picture was written and directed by Paul Hyett, a filmmaker who has shaped his career in parallel with the growth of the festival. He worked as special makeup effects designer on Simon Hunter's Lighthouse (aka Dead Of Night), which premiered at the inaugural FrightFest. "The moment I saw The Seasoning House, it had to be our opening film," says Alan.

Trailblazing the new is coupled with a nod to the genre's past. Italian horrror legend Dario Argento will take part in an onstage conversation with Total Film's Jamie Graham, while another rare treat promises to be Nightbreed: The Cabal Cut. This is a resurrected, re-edited version of Clive Barker's much-maligned 1990 feature - adding 50 minutes to the running time - restored by his friend Russell Cherrington after two European work prints were discovered containing additional sequences thought irretrievably lost. Alan Jones admits that he was "the one person who didn't want to show that. When it was first propositioned to us I couldn't see the value. I now hold my hands up because it's the one film everybody has told me they really want to see."

2012's guest list is rich with horror celebrity and the numbers are greater than ever. However, the third day promises to eclipse the usual attention with an injection of European glitz and glamour thanks to the world premiere of Federico Zampaglione's Tulpa. "We've got a lot of Italian press interest," notes Alan, "something we've never had before." In this case it's because they will have Claudia Gerini - Italian acting royalty and star of Tulpa - in attendance. "She's generating her own publicity campaign."

In 2011, Israeli filmmakers Aharon Keshales and Navot Papushado's Rabies (Kalevet) was the toast of the Discovery Screen. Two of this year's potential hits are Remnants and Before Dawn. "Remnants just blew us away," enthuses Alan of Peter Engert's haunting tale set after World War III has happened and the USA is in meltdown. In contrast, Before Dawn is a Yorkshire-based zombie flick written and directed by its unlikely star Dominic Brunt, better known as veterinarian Paddy Kirk in Emmerdale. "That's going to surprise a lot of people!"

A new addition is the Re-discovery Screen, which offers the chance to catch a few horror classics as they should be experienced. "I want to see The Devil Rides Out restored on the big screen. That's one of my favourite Hammer films of all time. And Bride Of Frankenstein - so many people have said how pleased they are we're putting this on because it's the one classic they've never seen on the big screen."

Other surprisingly recognisable names and faces at FrightFest include the Elijah Wood-starring remake of Joe Spinell and William Lustig's 1980 video nasty Maniac, plus Jennifer Lynch's purportedly unsettling Chained. Hailed by Jones as the "best film I've seen in years", the latter stars Vincent D'Onofrio (Full Metal Jacket, TV's Law & Order: Criminal Intent) as a cab-driving serial killer who raises a kidnapped child to be his sidekick.

It's a tough slog watching six movies a day from 10am through to 1am. Some will do that for five days straight. Some will come along for just one or two. Alan Jones: "I think the horror community, not just the FrightFest one, is a brilliant group of people. We sublimate our desires by watching this sort of stuff on screen, which makes us far better people."

This August bank holiday weekend lots of thrillseekers visiting the capital will ignore the media pull toward the colourful celebrations of Notting Hill Carnival and head instead to Leicester Square's Empire Cinema to catch what spews forth from the gates of movie hell. Stay tuned to tQ for a postmortem report by Cigarette Burns' Josh Saco.

Film4 FrightFest runs from Thursday August 23 to Monday August 27 inclusive. Limited day passes and tickets for individual films are still available; details can be found at the event website. To get in the mood, listen to Stuart Wright and Clive Ashenden's Gruesome Twosome podcast.