When venerable jazz fanatics get teary eyed intoning lists of departed heroes, listeners usually find their eyelids drooping. But not with Georgie Fame, the veteran jazz and R&B singer and keyboardist, who was almost in at the dawn of British rock'n'roll, and then devoted his post-hitmaking career to affectionate celebrations of bop and swing.

Fame's announcements are jazz-buffs' sermons - dispelling mythologies, crediting obscure arrangers, explaining the true roots of a famous tune. But in his offhand way, he always sounds as if he loves it still, and that's the infectious part. When Fame sings, he sounds like another member of the instrumental lineup. When he directs a band, it sounds as if it wouldn't matter if there were two, or 10, or 100 musicians, he'd still have the same relaxed relationship with them all.

This is the last week of a three-week run for him, but the week that packs the biggest punch. Fame relishes larger ensembles when budgets permit and this week's 15-piece plays with swaggering power, its solo strengths boosted by virtuosi, including saxists Peter King and Alan Skidmore, and trumpeter Guy Barker.

Fame strips lyrics of emotionalism and sometimes of literal meaning, but puts rhythmic recklessness and a speeding melodic invention in their place. On Peter King's The Woodshed (a bop tune built out of a Charlie Parker exercise with skids into Now's the Time and Salt Peanuts), Fame's tumbling lyrics mirrored King's fluency, and Benny Golson's Tuned Into You switched from a mid-tempo swinger to a zigzagging bop line that ended with a 1950s radio jingle. The waltz Dawn Yawn was dedicated to the place where Fame got famous - Soho's old Flamingo Club - and Jon Hendricks' lyrics for Count Basie's Little Pony were delivered faster than even Hendricks formerly negotiated them. An old hand with a young spirit, still at the top of his game.

· Until Saturday. Box office: 020-7439 0747.