At the opening night of his latest British tour on Tuesday, Rufus Wainwright rounded off a year-long charm offensive that has included a Glastonbury appearance, a Burt Bacharach duet and the latest reissues of his two Want albums in a double-disc package. Ever the mischievous showman, he arrived on stage dressed like a weekend golfer and finished the show in a dressing gown. From Bertie Wooster to Noël Coward via two packed, but uneven, hours of music.

For much of the set, Wainwright held the capacity crowd in the palm of his immaculately manicured hand. And yet, more than once, he dropped us with a jarring bump. There were vivid bursts of heart-stirring brilliance, mostly when the young songsmith sat down alone at the piano for rueful romantic ruminations such as This Love Affair and Poses.

As Wainwright’s band slowly coalesced around him, several songs departed from their studio blueprints. His achingly beautiful vignette of youthful love recalled in middle age, The Art Teacher, acquired a pleasing new bounce thanks to syncopated strings and brass. His mournful homage to the late Jeff Buckley, Memphis Skyline, was also expanded into a bustling miniature symphony.

However, there were also moments of laboured comedy and ill-judged amateur dramatics. Dawn French and Jennifer Saunders turned up for an ungainly gallop through Spotlight on Christmas, an inexplicable in-joke that left Wainwright looking faintly embarrassed. A new song about a failed seduction, Between My Legs, also sounded rushed and uncharacteristically clumsy.

Indeed, much of the show’s mid-section was marred by arrangements that drowned out the singer’s natural grace and wit with polished, over-ornate instrumentation. Although Wainwright clearly owes a debt to classic crooners and Broadway showtunes, it is a shame when his easy-listening muse eclipses his more edgy, ambitious, Radiohead leanings. He is at his best when playing to both sides of the road, not the middle.

The show’s grand finale was pure high-camp spectacle. After the whole band performed a wilfully amateurish dance routine in Roman togas, Gay Messiah was staged as a full-scale passion play. Clad in electric blue robes, Wainwright performed while two centurions bound him to a giant crucifix. It was mildly blasphemous pantomime, half Jesus Christ Superstar and half Jerry Springer: The Opera.

A shameless drag queen at heart, Wainwright’s charm offensive on Tuesday would have won over even the most hardened cynic. But his handsome, serious-minded songs could have been handled with a little more care.

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