An album that's been touted as far back as 2005, Portishead's Third had all the makings of a mammoth disappointment. A band notoriously casual when it comes to releasing albums (there was a gap of three years between their debut Dummy and its follow-up Portishead, and a gap of ten since their last release proper), the Bristol trio drummed up excitement last December, when they played their first full-length set since 1997 at the ATP festival in Minehead. Reports claimed that their new material was as innovative as ever - and despite its frustratingly long conception, Third delivers on its prolonged promise.

That's not to say that time has mellowed a band renowned for creating music born out of unease: Third is fraught with the agitation and tension that has informed all of Portishead's releases so far. The bookends of the 49-minute-long album (Silence and Threads) both encapsulate the shivering drama that usually soundtracks a spy movie, the former's controlled gloom proving particularly menacing; the detached dance throb of We Carry On is one of the most potent tracks here, while the stripped-back banjo/Beth-fest of Deep Water throws a curveball midway through the album. Gibbons's contributions, too, are as hypnotising as ever - her ghostly, barely-there vocals providing an apt foil to the cold, mechanical rap of Machine Gun.

There are no Glory Boxs or All Mines here, that's true; but if anything, Third is proof of a band who, seventeen years into their career, are still as innovative, off-beat and as subtly disquieting as ever.