There is a moment in Bo Burnham's show when, crossing the stage from guitar stand to keyboard, he breaks into a dementedly silly walk. "Never waste a moment," he barks; every second must be funny. He's mocking the mechanics of professional comedy – but also speaking true words in jest. There is no slack in this half-new show from the 20-year-old American who electrified last year's Edinburgh fringe; no chink in Burnham's armour, nor any let up in his fusillade of fiercely intelligent postmodern comedy.
That's mainly a strength: Burnham wants his audience giddy and off-guard. He gets many of his laughs from radical shifts of gear, from balladeer to gag-man ("If Jesus walks on water, does he swim on land?"), from reciting Hamlet to role-playing a dialogue with an invisible baby. You don't know what's coming next, or how you're meant to react. Top tip: dumb appreciation won't be welcomed. "I work very hard at my jokes," Burnham growls at us. "Do not applaud my improv."
He sounds like a brat, doesn't he? But Burnham is a step ahead, sending up, and singing about, his petulance and precocity, the egotism of art, and the conventionality of comedy. His punning lyrics are showily brilliant. There's a new number that samples and splices the schoolfriends and Hollywood agents trying to exploit his success. Burnham's perspective on fame and talent is breathtakingly cynical; there's more scorn in his show than affection.
That may change – he's still young, and tonight his maniacal pace seems (more than in Edinburgh) like a defence against self-exposure. He was also hard to hear: the sound quality, from my seat in the circle, was poor. But Bo Burnham half-understood is still more exciting than most of his peers. His talents, at music and meta-comedy, are dazzling.
