“Fangs whitened here,” said the sandwich board along Highway 101. It was the first sign of our approaching destination. As the tiny two-lane highway rolled on, the blood-sucking puns increased. Finally, on the town’s outskirts, a plastic banner said: “Now entering the Twilight zone.”

Welcome to Forks, Washington, population 3,120, currently under siege by vampires.

For millions worldwide, the city name evokes the location of the beloved Twilight book series — Stephenie Meyer’s teenage vampire love stories that spawned equally passionate (if corny) movies. Just like the film’s stars that became overnight sensations, Forks, too, has undergone a seismic personality change.

The former hard-luck lumber town, four hours (and a ferry ride) west of Seattle, is now a star in its own right thanks to the hordes of Twilight devotees who trek across the globe to pay their respects.

When Meyer picked the town to be the setting for her teenage vampire love story in 2003, she had not previously heard of it. Looking for an atmospheric location for an idea that came to her in a dream, she searched for the part of America with the most rainfall — voilà, Forks. The tree-covered landscape was the perfect location for her love story between Edward, the sexiest vampire alive, and Bella, a wonderfully awkward teen. A blockbuster was born and seared into the hearts of its teenage following.

The adulation is obvious as my guide joins a car chorus of brake lights at the rather ordinary “City of Forks Welcomes You” sign. The sign alone has become so popular that officials moved it off a nearby steep hill. “Someone was going to get hurt,” Nedra Reed, the Mayor, tells me. “I was having nightmares about getting sued.”

The small beating heart of Forks is full-moon mad. I’m instantly sucked into a mass of “Twilighters” as they hit the stores on the main thoroughfare. If one of the 18 stores is not entirely devoted to Twilight paraphernalia, it boasts a Twilight speciality. Jerry’s Lock and Key proudly carries a full stock of T-shirts. Each of the six restaurants has shelves displaying “Vampires Suck” shot glasses.

But no one better personifies the vampire excess than Annette Root, who used her savings to open two Dazzled By Twilight stores in Forks and one in nearby Port Angeles. She has organised the Twilight tour and runs the nearby Twilight Lounge. In the most impressive of the Forks stores earnest shoppers file past real high-school cheerleaders, fake trees and a mock gazebo with fairy lights just like the one that Bella and Edward danced on during their prom.

Root proudly rubs her hand through the artificial grass that carpets the entire place. She puts a hot-pink Stephenie Meyer power bracelet on my wrist. “You have to wear this for Stephenie,” she tells me.

Meyer visited once in 1996 to read sections of the book in the very park where Twilighters have gathered to honour her. But this weekend is anything but ordinary: it’s the high holy day for her devotees as the town celebrates an official day in her honour on Bella’s birthday.

“Since then it’s been boom,” Mayor Reed says. “Sonic boom.” The former schoolteacher proclaims Stephenie Meyer Day in a sing-songy voice as if reading a children’s book, loudly harmonises on Happy Birthday to an imaginary Bella, then helps herself to a piece of Bella’s birthday cake.

Like the estimated 2,000 people who have come to town for the celebrations on September 13 — from as far away as Germany and Japan — the Mayor, too, is happily geeking out in red and black attire. “My vampire outfit,” she gushes.

The reason for Twilight joy is clear as the “No Vacancy” lights flicker into life at all three bog-standard motels and the shoppers pull out Visa cards at thriving stores that had been vacant until months ago.

Meyer certainly adopted the whole area in her book. EverGreen Escapes, one ecotourism group that tours the area, has even searched out the thick, moss-covered forests for the best representation of the grass-covered clearing where Edward showed Bella how he sparkled in sunlight.

The city is surrounded by national park or lumber-tilled rainforests. The group also visits the rugged coastline of the Quileute Reservation in the tour, where the driftwood-covered beaches can be seen like the one that Jacob — the Native American with a crush on Bella — revealed to her. Also in the distance, the high cliffs from which Bella took her famous dive — not recommended for nonfiction human beings because of sure death in the shallow waters below.

Amid all the Twilight hoopla it is hard to find even a cranky critic. The skateboarders in the Forks park shrug when I prod them about Twilighters. “My sister took second in the Bella lookalike competition,” one admits.

Probably the only thing that the locals can complain about (and, believe me, I tried to find more) is the amount of traffic in a town that prides itself on having only one set of traffic lights.

A growing bloodlust comes over me as I seek at least one voice that might yearn for the good old days before Twimania, but even the local weekly newspaper, the Forks Forum, received only one letter in March decrying Twilight as “a demonic spiritual assault”.

Chris Cook, the editor of the Forks Forum, suggests that I hit the Friday-night bar scene. The logging men have been allowed to let the local brew, Rainier beer (originally produced in Seattle), do the talking. First stop is the sparsely attended Smoke House Lounge. The no-nonsense bartender croaks: “This has been a godsend for this town.” It’s all very rough and tumble, but overwhelmingly positive.

She directs me to the rowdy Mill Creek bar, where I work my way across the clumsy dancefloor to the bar — naturally it’s beneath a mounted shotgun. As the evening progresses not even the toughest tree-man crosses the Twilight line. Another reason might be the influx of female clientele since the series began.

The next morning I make my way back to Mill Creek to talk to the notoriously cranky bar and antique rifle owner. He has a camouflage hunting jacket, a thick goatee beard and a fixed, cross expression.

Through the cracked door of his bar, Rick Reeves reluctantly agrees to come outside and talk. I’m feeling good about this, even better when he grunts as if he’s about to punch me when I ask if he’s read Twilight.

“I tried reading that book,” he growls. “It’s no John Grisham, that’s fer sure.”

But as he talks about the new Forks, he softens. “I’d like to write that Stephenie Meyer a letter,” he says, “and tell her thank you.” He doesn’t flinch when I throw out a parting handshake and reveal a pink Stephenie Meyer bracelet. Everyone is a convert — even me.

New Moon, the second movie in the Twilight series, opens on general release on November 20

Need to know

Taking the tour EverGreen Escapes (evergreenescapes.com/twilight_tour.asp) offers the Twilight Rainforest Tour from the Kimpton Hotels in Seattle. The Alexis, Monaco, and the Vintage Park have Twilight packages for £172pp. These include pick up from the hotel, a ferry ride from Seattle, lunch, a tour of Forks, the beaches of the Quileute Reserve. Dinner with wine is served at Bella in Port Angeles, where Edward and Bella had their first date. A night at one of these three hotels (kimptonhotels.com) is from about £100.

Getting there BA (0844 4390787, ba.com) flies from Heathrow to Los Angeles, from £449.80 return.

Virgin Atlantic (virginatlantic.com, 08448 747747) flies from Heathrow to Los Angeles from £455 return.

JetBlue (jetblue.com) flies from Long Beach, California, to Seattle from about £85 return.

Car hire A week’s car hire from Los Angeles LAX airport costs from £120 with Holiday Autos (holidayautos.co.uk).

Further information Discover Forks Washington (forkswa.com). Dazzled By Twilight (dazzledbytwilight.com) offers two-hour tours for £24.

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