Melanie O'Reilly's music draws together a whole range of styles, from traditional Irish to jazz, but saying that doesn't begin to do justice to her - this is not some awkward, well-meaning fusion, but rather a focused, radically original approach that resists simplistic description. Backed by a four-piece band, O'Reilly's performance in Whelans was an intense, absorbing experience.

She has been collaborating for some time with the Irish poet Nuala Ni Dhomhnaill, and the concert began with settings of two Ni Dhomhnaill poems. Chugat an Puca started out like a conventional Irish air, but gradually the band joined in to create something very different - pounding drums played by Tom Dunne, Feargal Murray's keyboard harmonies, and Martin Nolan's whistle together produced an unusual yet totally apt accompaniment. Feis was characterised by dramatic, Tori Amos-like changes of mood and direction which combined well with the rhythmically unusual melody.

O'Reilly's voice is always at the centre, and she has a commanding presence. Technically perfect and capable of singing in any number of styles, she also injects songs with a rare depth of feeling and drama. The artlessly simple chorus of Annie Moore was rendered with an amazing emotional intensity. And for sheer virtuosity, her version of the reel The Hunter's Purse was breathtaking, moving seamlessly from a straight presentation of the tune into increasingly daring offbeat scat vocals.

O'Reilly and her band clearly do not work to any formula - no two songs or arrangements sounded the same. A genuinely original and exciting group.