Jack Whitehall, O2 Arena

My, what an entrance Jack Whitehall makes on the last night of his first arena tour. The 25-year-old - not that long ago making his Edinburgh Fringe debut - rides into the arena on a Segway with music blaring and fireworks. But he may have overreached himself, however, as a whole tier was curtained off and the remaining two were by no means full.

Whitehall has made his name as a posho comic who is always wrongfooted by his accent and his upbringing in a thoroughly middle-class household, and he continues to send himself up in Jack Whitehall Gets Around to great comedic effect. With his writers he neatly invents a world where he is downtrodden by his mum and dad, is obsessed with The Lion King (“Shakespeare with fur”) and his sexual exploits are routinely deflated by his lack of machismo (he tells us he routinely needs antacid during sex for his heartburn). The last is a neat case of having your cake and eating it – strutting your stuff for the women in the audience, but deflating your sex appeal so the men will think you're a great bloke despite your money and fame.

The show is in the round, which goes some way to making the huge space more intimate, yet Whitehall uses the big screens as well, looking into the camera to deliver punchlines and well timed asides. His observational material won't win prizes for originality - testicular examinations, train travel, super-hot microwave food – but he delivers it with verve. The occasional misfire – jokes about Muslims and Jews, and one about Wayne Rooney being stupid – are beneath him and landed, I'm glad to say, on stony ground.

So far Whitehall has played versions of himself in Fresh Meat and Bad Education (which he co-writes), but I suspect there's an actor of much broader talent in there, as displayed in his enjoyable Channel 4 show Hit the Road Jack and in this show when he successfully pulled off outrageously false stories.

However, for one one moment I thought I was back in Miranda Hart territory at the O2 only a few days earlier as Whitehall had his own – really, really true, I'm sure – story about a train lavatory door opening unexpectedly while he was mid-wee. Perhaps only buffoonish comics without any original material can't understand the operating instructions. Even less convincing were his deliberately bad accents and his pretend memory lapse of the payoff to a big routine.

There's no doubting that Jack Whitehall is a very likeable and talented performer who can tell a good story - but I'm not sure he's ready for arena comedy.