Wildlife campaigner, populariser of orchestras, now Beatles tribute act. Is there no end to Bill Bailey’s renaissance man credentials?

Last night, nearly 5,000 children gathered to sing Fab Four songs for charity, and while most of the parents in the audience spent the gig playing spot-the-offspring, the highlight for comedy buffs was Bailey’s brief appearance.

“One of the kids backstage asked me if I was actually in The Beatles,” said Bailey before launching into a close harmony rendition of Things We Said Today with regular chum, the actor Kevin Eldon. While it was fairly faithful, Bailey could not do it completely straight, strumming bouzouki rather than guitar.

This was not quite as comical as the Spinal Tap show Bailey had been to on Tuesday. The comedian should have heeded that lesser-known WC Fields motto: “Never perform benefit gigs with animals or children.”

He was inevitably upstaged by the massed choir’s renditions of classic hits from Please Please Me on. “I love these intimate little venues,” he chuckled as he looked round and saw backing singers stretching towards the heavens.

What the children lacked in tonal precision they more than made up for in synchronised charm, all donning shades for Good Day Sunshine or spectacularly opening umbrellas as a group of non-singing performers acted out The Beatles’ career from Hamburg to hippies.

Good wholesome fun, though judging by Bailey’s facial hair I Am The Walrus might have been a more apt choice of cover version.