Horror films are essentially adolescent. Perhaps you are working your way through the Saw hexa­logy, anxious for Saw VI to reveal Jigsaw’s complex saw-based philosophy. It’s safe to say, though, that you won’t be keeping that box set on your shelves when prospective partners or in-laws pop round. Like all things adolescent, they’re best kept under the bed.

Vampires are different. Vampire movies transcend their blood-soaked genre in ways that werewolves, mummies and even the misunderstood progeny of Dr Frankenstein can only dream of. Each generation plunders the bloodsuckers’ coffin, pulling out symbols and stories to retell in urgent contemporary narratives that draw in politics, culture and — of course — sexuality.

“Vampire stories were created when it was impossible to write about sex openly, so they arrived laden with sexual metaphors,” says the psychologist Andrew Bates. “At the same time, I think they deal with more existential themes: what happens when you die and how it feels to be the outsider. That’s why they’ve survived the opening up of sexuality in art — although they’ve had to face some pretty grim ironic retelling along the way. Today, there’s a huge mainstream interest in the romanticism of longing and losing they represent.”

Indeed, this year, fangs have been worn with gothic beauty and a sense of impossible love, from the teen-sensation books of Stephanie Meyer to the Swedish art-house film Let the Right One In. Joining these aching portraits of isolation and desire is True Blood, from HBO and the pen of Six Feet Under’s Alan Ball. In True Blood’s hyperreality, vampires have come out of the closet, now they can slake their thirst on synthetic blood. They’re living alongside us, claiming civil rights and rubbing shoulders uneasily with their fans, detractors and implacable opponents. And at the heart of this wry sociopolitical comedy there is, of course, a love story.

Sookie Stackhouse, played by the Oscar and Golden Globe­winner Anna Paquin — with the tumbled blonde tresses and wary sensuality of the teenage Britney, before the nightmares came — is a waitress in a bar in Bon Temps, a sultry Louisiana town with a small vampire ghetto. One night, 173-year-old Bill Compton — played by the British actor Stephen Moyer — walks in, and her composure deserts her for ever. Compton is a quiet, still vampire with bottomless eyes and a soft, old-school Southern drawl.

Sookie can read people’s minds, which is why she’s still a virgin: every time she’s come close to a man, his thoughts have scared her away. Compton is the first whose mind remains hidden, whose ideas and thoughts are unpredictable, and it’s for his mind that she loves him.

Of course, things go wrong from the beginning. The confusion, pain and fury of impossible love is at the heart of the drama. They have to be together, but they can’t be together, and the aching inevit­ability of their defeat underpins every charged conversation. The chemistry is palpable and has boiled over into real life, with Moyer and Paquin admitting this ­February that they were dating. “When I got the job, I was flown over to Alan’s offices, met Anna, and we just clicked,” Moyer explains. “It was incredible. Like a kinship.”

At this point, you might be forgiven for thinking: “Blonde girl, vampire, forbidden love — that’s, like, so totally Buffy.” Trust me, it isn’t. The steamy beauty of True Blood’s Southern gothic setting pulls us away from high-school clowning, and HBO’s cable status allows for story lines that would make Sarah Michelle Gellar blush. Vampire sexuality is to the fore — they have human love pets, ambiguous morality and blood that can induce four-hour erections if a man takes just a tiny sip. As a result, in a cute switcheroo, unscrupulous dealers who know V-Juice’s worth to the sexually inadequate hunt vampires for their blood.

Ball came to the show through the Sookie Stackhouse books, a series of novellas set around the affair between Sookie and Compton. “I bought the first book — a total impulse buy — and I couldn’t put it down,” he explains, sitting

in the fake studio setting of a decaying wooden porch near the Louisiana swamps. “I loved the world, I loved how funny it was, how sexy and romantic and dramatic and scary. Vampires are sexy. They live for ever, and they’re not constrained by conformity and traditional moral codes. You can live vicariously through them.”

In Sookie’s world, vampires are clearly part metaphor — a group with blood and sexuality issues, struggling for acceptance and civil rights from society in the face of a hostile Christian right, but still needing space to party in a way society might not understand...

“Well, yes, I’m gay, and I grew up being aware of that at an early age, in a fairly repressed family,” Ball agrees. “Nobody in my family was ever naked in front of anybody else. I know what it’s like to be struggling with these feelings and to have these desires for sexual contact, and at the same time to be feeling I shouldn’t be having these desires, it’s wrong for me to feel this way and has to be kept a secret. That’s partly why I responded to the books — because I thought it was clever. They can be a great metaphor for any feared, misunderstood, disenfranchised group.” He grins. “On the other hand, you better not get in their way.”

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