The fake foliage hanging from the Eve Club's ceiling gives it the air of a woodland glade. This is one of those gatherings in which the best one can hope for is to remain inconspicuous. That is exactly what Portishead try to do: standing around chatting while the DJ makes mellow, then melting out of the crowd and onto the cramped stage, performing a handful of songs from their superb dbut album, Dummy, and merging modestly back into the throng again. Miraculously, given the complexity of their music and the fact that this (excepting two show-stopping tunes on Later and one brief showcase in a Clapham tea-room) is its first public airing, they sound even better in person than they do on record.
Singer Beth Gibbons is barely visible, ducking down beneath the level of the front row of heads, and appearing mainly as a plume of smoke coming out of a bald man's ear. There's no over-looking her voice though - it's smooth as Sade one minute, rough and raw as Poly Styrene of X-Ray Spex the next - and it cuts though the keyboard splashes and the loping bass like an ambulance through a traffic jam. The drummer's muted clank is half man, half machine, and unassuming 37-year-old guitar wizard Adrian Utley cranks out fuzz communiques Ennio Morricone might have written for Jimi Hendrix. Behind it all is the precocious 22-year-old Barrow. He crouches studiously over his turntables, using them as a musical instrument.
It's the twists and turns - the subtle shifts, the subterranean moodswings - that make this music so beguiling. If Portishead have a problem at the moment, it's an excess of mystique. This is partly their own fault, for doing everything so stylishly, but it would be a shame if their drama and complexity got washed away in a tidal wave of noir hyperbole: all smoky rooms and small-hours drinking. Portishead's music is alive: it should not just be the preserve of soundtrack obsessives and ambience- chasers.
Until now, the band's press encounters have followed a pretty strict pattern. Reporter arrives, singer leaves, often with a squeal of tyres from her Triumph convertible. This time it's different. I arrive at the appointed place - a small terraced house in a less than leafy part of Bristol. Geoff Barrow, it turns out, is ill with a suspected ulcer (he worries too much) so Beth will do the interview. Her matter-of-factness, I later discover, is in sharp contrast to the feelings of her record company, who had been planning to use Beth's first exclusive as a bargaining counter for control of North Sea oil revenues.
Cheerful and chatty, wearing glasses not contacts and speaking with a light West Country burr not a tortured torch croak, Beth Gibbons is in a good mood. Portishead's second live appearance of the week - at the Transmusicales festival in France - was much more fun than the London date, which despite everyone else's opinion they do not consider to have been a great success. Next to her passport and money on the table in the kitchen is a hand-written note from a member of the audience. It says: "You were wonderful - thank you for the pleasure you gave us."
For a band whose music wasn't, as both Geoff and now Beth have made clear, "designed for live", Portishead seem to make a big impression on everyone who sees them. Does she enjoy singing for a crowd? "I get very nervous," she says, "but I like the idea that people who are listening to us can see us." She doesn't mind admitting that nerves have made two vital contributions to her stage persona - chain-smoking and hanging onto the mike-stand as if the floor was being pulled away. "We're not there to be a dominating force," Beth continues, "I don't like it when bands go: `Look at us - enjoy it.' You might not want to enjoy it. You might be feeling ill."
On the strength of a few gigs with a boyfriend's band seven or eight years ago - her Janis Joplin phase - Gibbons has often been portrayed as some kind of grizzled pub-rock veteran. But until the fateful day in 1991 when she bumped into Barrow at an Enterprise Allowance scheme induction day, her quest for potential collaborators had been a thankless one. "I went to his house and played him some of my stuff," she remembers, "and he came round to my house and played me some of his." Common ground - he a teenage hip-hop fan, she an unrepentant, mid-twenties song-lover - was not extensive. But, says Gibbons, "he was obviously good". And when he converted some of her rough ideas into "a proper song" she was truly impressed.
Their beguiling blend of classic songcraft and eerie studio atmospherics grew out of a tortuous writing process. Geoff would go into the studio with guitarist Adrian, drummer Clive and anyone else he needed, record on digital tape, take out the best bits and put them on vinyl, then scratch- mix the results back on to tape, "to enable him to put his own style onto the playing". Only when this tricky process was complete was Beth free to add her vocal lines - tune first, lyrics after - in the privacy of her own home.
For someone who "never particularly wanted to be a songwriter" she shows an impressive facility. Portishead's next single is a prowling, snarling panther of a song called "Glory Box". Despite being a heartfelt plea for sexual equality - "Move over and give us some room" - based on the common- sense proposition that "men should give women a reason to be nice to them", this song has already been misinterpreted by at least one observer ("It was funny," Beth says indulgently, "because he was a man") as a demand for a return to more traditional masculine and feminine roles.
"People think it must feel great when everybody loves you all of a sudden, and it does," Gibbons admits, "but there are other sides to it. I don't feel like this now, but at one stage I was thinking you write songs and you hope you're gonna communicate with people - half the reason you write them is that you're feeling misunderstood and frustrated with life in general. Then it's sort of successful and you think you've communicated with people, but then you realise you haven't communicated with them at all - you've turned the whole thing into a product, so then you're even more lonely than when you started.
Beth Gibbons' current attitude - "music is a spiritual thing and it should be treated that way" - seems at odds with such a pessimistic view. Blithely asking "Would you like to hear some stuff?" she rifles through a pile of discs and DATs to find the front-room demo that she played to Geoff when they first met ("My mum still wants us to release this as a single"), an assortment of dummy runs for songs on Dummy ("This is where I tried to rip off Sinead O'Connor") and even ("I don't think he'll thank me for this") some of Geoff's early studio experiments.
A few days later I get to talk to Mr Barrow on the phone, live from his bed of pain. His physical discomfort is as nothing to the thought of a total stranger being given access to his formative moments, but he is man enough to laugh about it.
"You don't want to make an aura round anyone," his singer had explained, "because it's just not fair on that person. It's unfair and unrealistic and it makes the audience stupid. It only happens out of ignorance and because the media wants things that way; and I think the audience should be told that it's not like that."
8 `Dummy' (Go! Beat, CD/LP/tape) is available now. `Glory Box' is released on 3 January and Portishead will tour when they have to.