Massive Attack are back. And right now, at a time when anodyne celebrity obsessions and endless Popstars juggernauts are monopolising the cultural landscape, we need Britain's most influential band more than ever. Massive Attack have consistently pushed the boundaries of both their own sound - twisting their soundsytem roots into the complex, insistent guitar layers of Mezzanine - and constantly surprised with their inspired collaborations and groundbreaking art direction. Even now, twelve years after they first inked a deal with Virgin to release the landmark Blue Lines, promising artists are still referred to as 'the new Massive Attack.' They've stamped their mark on British music, shaping and shifting dance music, pop, British hip hop, drum & bass and rock - and the creative whirlwind is about to be unleashed again.

Massive Attack100th Window, then, is Massive Attack's fourth album. Written and recorded at the band's Bristol studio over the last year, it is also a giant step into warm glitchy electronica, psychedelic landscapes, Arabic strings and deep into the depth-charged dub reggae of old. Robert Del Naja - better known as 3D - explains: 'We wanted to make this album warmer than Mezzanine, but we didn't want to make it softer. We wanted to keep the edge and the intrigue, but without making it bleak.'

The album was written and produced by 3D and Mezzanine co-producer Neil Davidge, while Massive Attack's other member Grant 'Daddy Gee' Marshal took time out from the studio. 'Grant has taken a bit of a holiday, a sabbatical, because he's had a child, and he's been starting a new life,' says 3D. 'He'll get back into the swing of the music again when he comes on tour with us. He'll be back.'

Like all their releases, 100th Window is an inspirational, mood-altering panorama, propelling the band into new waters. 'We have always wanted to do something different and stretch our imagination and it was really important for us that it represented a shift forwards from Mezzanine.' The Bristolian band have always dovetailed brilliant songs with experimental music, and 3D decided it was time to get back to basics. He sung on four songs and hooked up with Sinead O'Connor. They recorded three tracks, including the dark, soul-dusted single, 'Special Cases'. 'She's one of the only great singers around,' says 3D. 'She brings total raw spirit to it, and a real emotion, a real belief in what she's doing. We're looking at the result of generation of nurturing which has made singers much more bland and generic, but she's angry.' The title was taken from cult electronic security book, written by Charles Jennings.

'I really liked that idea,' says 3D. 'The record is about the way that people try to keep their feelings hidden, but that there's always a way in - if you knowhow to pick the lock.'

Massive Attack formed in 1987, around their influential and legendary Dug Out club and Jamaican-style soundsystem. The club played a groundbreaking blend of hip hop, new wave reggae and early house and techno which shaped their hugely acclaimed 1991 debut, Blue Lines. Second album Protection featuring Tracey Thorn and produced by Massive Attack and Nellee Hooper, was released in 1994 and was similarly well received - and like Blue Lines sold over two million copies. Mezzanine was released in 1998 and apart from selling three million worldwide, took the band in a new, guitar-led direction - and contained the sublime 'Teardrop' featuring Cocteau Twin Liz Frasier. In the four year interim - after founding member Andrew 'Mushroom' Vowles left the band - the band went back to work, collaborating with David Bowie on a cover of 'Nature Boy' for the Moulin Rouge soundtrack, focusing on the bands on their Melankolic label and Del Naja did a rare remix for The Dandy Warhols on 'Godless'. 'We weren't in a hurry,' says 3D. 'And anyway, when was there ever a sense of urgency with us?'

Massive Attack's extraordinary vision continues unabated: The band are already writing new material, collating songs for the next album, which they intend to release within twelve months of 100th Window, and there are plans to work with Tom Waits and Mike Patton from Faith No More, and to repeat the success of this year's 'I Against I' collaboration with Mos Def. So to the music. Opening track 'Future Proof' is multi-layered and moody, fusing deep electronica with a landscape of rolling bass and drums.

Massive AttackMassive Attack's long-time collaborator, Horace Andy - who first guested on Blue Lines - appears on edgy, echo-chamber lament 'Everywhen' and the unsettling 'Name Taken.' Whilst the band has always flirted with Eastern sounds, notably on 'Karmacoma' and 'Inertia Creeps', they've taken the sound to a new, striking level. 'I really love the sound of eastern strings - they contain a raw, beautiful emotion. The current state of the world has rubbed off on the record. You can't help feel that the west is dominating the east and I wanted to bring some of those emotions into the record.' The seductive, starry 'Small Time Shot Away' is stoned and insistent, and features 3D on vocals. Closing track, 'Anti-Star' powers along on crackly, static energy and epic, Arabic strings, and like the entirety of 100th Window, perfectly mirrors dance music's history of cultural hybridisation.

The record almost leapt into a different sonic universe: The band recorded hours and hours of 'staggering and trippy' music with ex-Spiritualized outfit Lupine Howl but after weeks at the mixing desk, stripping the music down and reforming it into usable songs, they started again from scratch. 'We had about 80 hours of amazing jams, but they weren't right for us. Once we cleaned them up, we lost what made them special.'

As well as a worldwide tour, which will feature giant, interactive LED screen, Massive Attack will be throwing four one-day events over the summer. 'When we first started we always tried to create an environment around the soundsystem, and create a place we wanted to perform in. Now we want to get back to that again and have a great party in the process.' A DVD of short films and animations is also due next year, cementing the band's reputation for ahead-of-the-curve artwork. If Popstars and Fame Academy represent the triumph of what 3D calls 'karaoke culture' then 100th Window strikes a knockout blow for the things that really matter: for beautifully-packaged creativity, for having an opinion, but most of all, for the music.