On stage, he stomps around in seven-inch heels, spurts blood, and breathes fire. Off-stage, he has a relaxed yet authoritative manner, and a penchant for long, trumpeting monologues rich in sound-bites. As he flits from American media imperialism to the meat-and-potatoes of bedroom conquests - he now claims to have slept with close to 4,000 women - one quickly realises that he's a smarter cookie than can be expected from the simple double entendres of "Calling Dr Love". "You know the media laugh at us," he continues, "but it's not the media, the intelligentsia, or the back- room politicians who determine what the people want. They want McDonald's, they want Coca-Cola and they damn well want Kiss."
It was the Israeli-born Simmons who formed the band with fellow New Yorker Paul Stanley back in 1972. By the middle of that decade, Kiss had become a paradigm of American adolescence. Their make-up defined personas - part super-hero, part rock star - were enchanting. Their shamelessly grandiose stage shows, and glam-rock influenced anthems struck a universal chord. When they released the Alive! double-album in 1975, their record sales began to eclipse those of Led Zeppelin, the rock gods of the day. In 1994, such eclectic talents as Stevie Wonder, the Lemonheads and Garth Brooks were among those who paid homage to Kiss on the tribute album Kiss My Ass, and more recently, a certain Mrs Love recounted how her daughter Courtney had shoplifted a Kiss T-shirt when she was 12. Kiss are loved, cherished even. They are the anti-fashion rock behemoth that will always put bums on seats. As Simmons himself puts it: "We're like Godzilla, and, believe me, Tokyo will get crushed."
The fans in Helsinki are as excited as anyone else at the prospect of seeing the classic Kiss line-up (reinstated since guitarist Ace Frehley and Peter Criss returned to the fold for an MTV "Unplugged" concert in 1994), back in full make-up and sorted for pyrotechnics. I met Pekka - a young Finn who works at Heathrow airport - on the flight over. He told me that, while his English girlfriend is really into drum 'n' bass, it's Kiss's Lick It Up that still hits the spot for him. At the venue itself, legions of fans arrive with their faces painted like their idols. One notices, too, that although the hard rock gig is supposedly the last bastion of the acne-ridden lad, there are vast numbers of highly attractive Finnish Lolitas in attendance. These are the same girls who will later wolf-whistle at the video-screen shots of 47-year-old Gene Simmons's pulsating crotch, the same girls who, as "I Was Made For Loving You" builds to a crescendo, Paul Stanley will remind: "Until you scream, I'm not finished."
Simmons says he thanks God for the girls whose Wonderbras are lifted and pointed in his general direction, but adds that the stage is a shrine and all are welcome at the electric church. He's the consummate interviewee, but then he's had plenty of practice. I'm grateful when he eases up on the verbal bombast and begins showering me with gifts instead. I get a copy of the Kiss magazine, Kiss sweets, and a Kiss baseball cap. I even get a Kisstory book, a weighty, personally-autographed tome which retails at $158.95. ("What did you do - blow him?" asks Doc McGhee, the band's manager, post-interview.) "I love these too," continues Simmons. He's now drawing my attention to an advertisement for Kiss action-figure toys on the magazine's back cover. "I'm so glad I'm not in REM," he says. "I mean, they're a band I respect, but don't try and tell me they have this much fun with their merchandising."
The stage-show - a truly flabbergasting sonic and visual tour de force - is a triumph of imagination over logistics. There's Frehley's rocket- launching guitar. There's the Krakatoa-like flash-pot explosions - so bright they burn a flaming-orange after-image on your retina. At one point, Paul Stanley flies out over the crowd while singing "Love Gun".
Stanley is a well-preserved character, engaging and articulate, and the metallic-silver Kangol beret atop his flowing locks lends him a slightly camp air. When I suggest that there's no point in poking fun at Kiss because there's such an obvious element of self-parody about what they do, he's not in the least offended. He does have a counter-argument, however. "Are we over the top? Of course we are. But we have a tremendous amount of pride in what we do; much more, in fact, than many of these so-called `credible', `progressive', or `sincere' bands. We have great fun doing what we're doing, but this is not a free-for-all and it's not a lark. That would be disrespectful to our bosses, the fans."
Kiss's professionalism is also evident in the way that both Simmons and Stanley field my interview questions. You can't ask them anything that they haven't heard before, and sometimes you feel that you're getting the party-line, rather than a spontaneous answer. The more you talk to them, though, the more you have to admire their savvy. Surely there must be moments when he catches himself in the mirror with the make-up on and feels ridiculous, I ask Simmons. He shakes his head quite slowly and deliberately. "Better ask Santa Claus or Superman the same thing. I'm enchanted by my stage persona, and the magic works on me every time. It's only ridiculous if you don't believe - the same is true of each and every religion."
I also ask them about the double entendres; about the plaster-casting groupie who wants "your love to last her" ("Plaster Caster"), about "Love Gun" (since 1977, Stanley has been claiming that you pulled his trigger). I want them to concede that they had a good old belly laugh when they wrote those lyrics back in the 1970s. They won't, of course.
"To me, there's nothing more pompous than a singer-songwriter who thinks that, with fame, comes an intellect transfusion," Stanley tells me later. "When I write a song I have no interest in showing you what my IQ is, because rock and roll is music of the crotch, not the cranium." Through the open door of the tiny room in which Stanley and I are sitting, I can see into the inner-sanctum of the dressing-room proper. Gene Simmons, still in full make-up, is holding court with a gaggle of Finnish nymphets.
So what can Kiss's British fans expect at Finsbury Park? "Basically, you're going to experience another Blitz, but this time, it will be from the ground up," Stanley says. "The fireworks will literally reach 1,000 feet into the air. We want to kick God in the butt".
Kiss headline the `Kaos in the Park' festival at Finsbury Park, London tomorrow. Booking: 0171-344 0044 / 0800 13 888 66; `Greatest Hits' are available on Polygram