Like Dianne Reeves last November and Madeleine Peyroux in April, Cassandra Wilson creatively tuned in to the intimacy Ronnie Scott's club offers to finely nuanced vocal stars usually confined to big stages. Looking at ease and sounding even more so, Wilson wafted resonantly through two decades of her repertoire with a congenial quintet including her alter ego, guitarist Brandon Ross, and the expressive Swiss harmonica player Gregoire Maret.

Maret opened the performance with an original, in which his vocalised harmonica tone and plaintive high notes shimmered through the room before a wistful melody swayed over the warmly acoustic sound of this typical Wilson lineup. The star then emerged to wrap her opulent low register and leisurely tone-bends around Children of the Night from her Blue Light 'Til Dawn album of 1993. She changed the gender of Willie Dixon's Hoochie Coochie Man but kept its air of spine-tingling expectancy, set double-bassist Lonnie Plaxico fluttering through an intricate intro to No More Blues – a vehicle for long free-rolling breaks from Ross and from pianist John Cowherd – and eased into an account of The Man I Love that began engagingly playfully but wound up a shade becalmed.

Wilson's delicate whimsicality, and the reflective disposition that unquestionably fuels her formidable talent, can occasionally let songs flatline longer than they should. But with Seven Steps to Heaven (from 1997's Travelling Miles) she took off into quick, sensuous swing peppered with glancing improvisations, sang a beautiful Wichita Lineman down low, a casually loping Last Train to Clarksville – and came back for a softly rapturous Time After Time in which Maret's harmonica lines curled around her like smoke. Wilson doesn't always open a window on her soul quite as far as her technique and remarkable sound imply she might, but that reserve is often part of the attraction.

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