Johnny Dankworth / Cleo Laine, The Stables, Milton Keynes

Thank heavens for second halves. Maybe the band has had a tipple; maybe the audience has. Possibly it's a different calibre of performer; conceivably, everyone - performers above all - has relaxed.

Not that John Dankworth, veteran of five decades of jazz at the top, needs to relax. At The Stables in Wavendon, the stylish village concert venue outside Milton Keynes, where he and Cleo Laine have created a Mecca for jazz-lovers, he's at home. She teases the audience like one of Julie Walters's Mrs Mop creations, while he plays amiable old codger, peddling self-deprecating anecdotes and pottering about like a retired guards officer. But let him pick up clarinet or tenor sax and you're in the palm of his hand.

We got that burst of vintage Dankworth when he and his band grabbed two slots and reeled off the theme music for Modesty Blaise (nice touches of trumpet and trombone/tuba counterpoint) and a glorious 1950s "Back Home in Indiana" arrangement. The band, who after frenetic rehearsal blasted or sleepwalked through part one, at last found their métier: brass and saxes choreographed as one, laced with gritty swing and rhythmic brilliance. Earlier, it was when the textures were pared down to flutes and paired saxes, or a combination of light, nifty drums and Alec Dankworth's stylish double bass, that the band found the spacing, breathing and undertow that good jazz demands.

The vocalists were mixed. Two Brit-award nominees - the rising young pop names Lemar and Amy Winehouse - had as much stage personality as a limp kangaroo. Lemar can verge on vocal banality, yet when he arches into a high falsetto, or catches a hint of syncopated rubato, a talent peers through. "Another Day" had real potential; his full-bodied "bonus" retake of "Fly Me to the Moon" was terrific. Winehouse's "Lullaby of Birdland" felt short on conviction, but she served up an "I Should Care" full of yearning pathos that was one of the evening's best items.

Like Winehouse, Jacqui Dank- worth fares best in the lower ranges; higher up, she misses her mother's sparkling finesse - so evident in Laine's cannily turned "Rockin' in Rhythm", gamely delivered as an all-too-brief concert farewell, wrapped in a mesmerising JD sax solo. But Jacqui scored a blinder with "Gentle Rain", a wistful number that gorgeously captured the pangs of youth .

The show's star turn was a young jazz saxophonist, Denys Baptiste, an articulate performer who manhandles his audience with slick intelligence and the deftness of a stand-up, and wields his tenor sax with the flair of his idol, Sonny Rollins. "Sunny Gets Blue" was slightly prosaic, yet still melting; his own "Be Where You Are" got a bit verbose. But "St Thomas" ("Not the Apostle; the island") was a gem, with a firm emotive pull.