Through the dry-ice choked stage loped Glenn Gregory, accompanied by the New Romantics' favourite mood-setter, the droning synth bass note. Behind him at the controls, Martin Ware and Ian Craig Marsh did their best to exhume the tradition of pursed-lipped deadpan, but Glenn wasn't going to stop grinning for anyone.
If you happen to have a song called "(We Don't Need This) Fascist Groove Thang" in your repertoire, there's no point being shy about it. Its overt political stance and Gregory's haranguing tone never detracts from its groovy danceability - "Don't just sit there on your ass / Unlock that funky chaindance" - and the audience got what they came for.
The numbers from 1981's Penthouse and Pavement and the following year's The Luxury Gap ooze this brash confidence, lyrics full of exhortations ("play to win", "do it right, do it wrong / Console yourself that either won't last long"), austere beats and awesome melodies. Heaven 17's new album, Bigger than America, has tried to mobilise their old techniques (just analogue synths - how demode!) to recreate the classic template. But rather than bold, public manifestos, their new concerns - "We Blame Love", "Do I Believe?" - are coming to terms with loss, the politics of the personal. The end-product is strangely uninvolving, complacent in its reappropriation of a winning formula. The crowd knew it: each time a new track was played, the momentum of the evening was lost.
They had, after all, come to do nothing more profound than hear their favourite tunes, reminisce and ask themselves what drove them to the fantastic excesses of frilly shirts and pale blue eye-liner. Which is why "Let's All Make a Bomb" proved to be the evening's pivotal song. Its ironic gloss on those early-Eighties preoccupations, consumerism and the arms race - "Let's celebrate and vapourise" - captured an era perfectly, and its unyielding repetition drove the audience into a frenzy.
You could argue that this proves that by finally playing live, Heaven 17 are creating nothing new, just pandering to an empty nostalgia, an opportunity for a singalong, arms aloft in shared ecstasy. But Glenn Gregory's voice is as resonant as ever; the songs still sound fresh and contemporary dance music is in their debt; and who could deny the mock-soul exuberance of "Temptation"? OK, they're not the vanguard of modernist pop any more, but with songs this good, why keep them in a museum?