You have got to admire Bill Bailey's work ethic. On Friday his run in Pinter's People at the Theatre Royal closed, on Saturday he was fronting the BBC Concert Orchestra in Watford, due, he quipped, to an clerical error which meant that "Vanessa Mae is currently doing stand-up." The musical departure was certainly more successful than his theatrical foray, even if the execution never quite equalled the ambition.

This is hardly a completely new string to Bailey's bow. He has always included songs in his sets, but here the melodies were impressively fleshed out. His pocket rock opera The Leg Of Time became a concerto complete with epic prog-rock chords and a cockney knees-up chorus, while Insect Nation, his saga of humanity being enslaved by angry ants, was enhanced by some beautiful mock-bombast.

Over the two hours though, Bailey, aided by conductor/arranger Anne Dudley, did not quite have enough superlative material. Much of the opening section was spent laboriously creating gags for specific instruments. The Bee Gees on disco bassoon was blissfully funny, but the second-half payoffs did not fully justify the lengthy first-half set-ups. Elsewhere Classic FM standards bemused an audience primed for non-stop laughs.

It would be churlish to criticise Bailey too much. There was certainly a sense of event here, with the star displaying a diverse range of talents. As well as telling some cracking stories and jogging about like a jolly goblin, he played everything from telescopic Alpine horn to spooky electronic theremin. The impish gagsmith is often likened to lugubrious mirthmaker Victor Borge. After this multi-instrumental marathon, record breaker Roy Castle is a better comparison.

Tonight, QEH (0871 663 2500; www.southbank centre.co.uk)