Somewhere between a female Bob Dylan and Elvis Costello, but with the voice of an angel (albeit a seriously pissed-off one), Thea Gilmore is currently Britain's best songwriter. And by a good few light years. "Avalanche" is her fifth album, and also her best, with Thea spitting vitriolic gobs of fire at the plasticity of modern culture and the resulting public apathy with fierce directness and an unflinching eye. Developing the soundscapes of her earlier "St Luke's Summer" and "The Dirt Is Your Lover Now", Thea and producer-extrodinaire Nigel Stonier add a layer of loops and effects to her usual chiming guitars and deceptively catchy tunes. "Pirate Moon" and the haunting title track ring with a sinister, trottled beauty - fluid and graceful, yet shot through with a creeping menace. "Mainstream", meanwhile, and "Rags & Bones" (probably the best song she's ever written) crackle with a barely-controlled rage, spiky and brutal as Thea goes for the throat. Then, sung in her most delicate, heartbreaking voice, "The Cracks" prophecises a forthcoming armageddon with more unflinching clarity of anything this side of "Hard Rain's A-Gonna Fall". This is potent stuff: a landscape where religion is obsolete ("Have You Heard?") and love a precarious thing ("Razor Valentine"); the young are listless and self-obsessed ("Juliet") and the media calculatingly enforce this ("Heads Will Roll"). However, if all this sounds rather depressing (and it is - this is real life, mate), Thea's level of passion, eloquence, anger and commitment mean that the songs are ultimately life-affirming and positive. This is real protest music for the 21st century, not the moany dirges of some jumped-up madam that are endlessly peddled elsewhere. Indeed, amid the corporate mush that passes for pop-music today (and don't tell me Oasis isn't as carefully packaged as Will Young or Avril Lavigne isn't just Britney holding a guitar), finding such an inspired songwriter with something fundamentally important to say is remarkable. And that she does so with such eloquent lyrics and brilliant melodies is nothing short of miraculous. "Are you gonna swim the mainstream/or are you gonna make like lightning?" she demands halfway through the album, in a flick-knife voice. But she has already made her decision. And what spellbinding lightning it is. No amount of superlatives do this album justice. Believe me, it's that good.