Once a comic has done his time mocking the follies of youth, it’s time to move on to the infelicities of middle age. Dylan Moran copped to this sooner than most: the tousled Irish comic has been behaving like a dissolute, despairing 40-year-old for a decade, even though he turns 38 tomorrow.

But all that practice has paid off. When I first saw this show a year ago, it was a bright, beguiling but faltering attempt to look at finding meaning in a godless universe. On Friday, in the first of its six weeks in the West End, it didn’t falter for a moment. This is stand-up comedy of the first order.

Moran takes his atheism as a question, not an answer. If religion is just there to shield us from death, as he reckons, how do we protect ourselves without that shield? Have relationships? Get hobbies? Worship the iPhone? He mixes a philosopher’s yen for meaning with a hedonist’s yen for meaningless fun in a comic approach that’s both intellectual and base, both innocent and irritable. “Shut up!” he cries as the audience intrudes on him with a laugh. “I don’t need your filthy approbation.”

Many of his topics should be clichés — women are more interested in curtains than men are; cereal is “dust with milk”; being a father is constant work — but they appear fresh thanks to his appalled attitude and his accurate aim. He’s trading in a curdled romanticism that’s easy to connect with, even as he takes it to extremes. We want the good stuff, he tells us, nibbling on some chocolate because he’s not allowed to smoke. We want sex, comfort and booze. Mornings, responsibility, watching bits fall off your body? Oh, must we?

Moran talks the talk of our uncompromising inner voices. He looks casual, sips some white wine, slurs his speech slightly as he powers out his ideas, seemingly on a whim. But behind the offhand rage, there’s scarcely a word wasted. He gets into a topic, develops the perfect image — Silvio Berlusconi, he tells us, is so corrupt that “every time he smiles an angel gets gonorrhoea” — then moves on. It’s lyrical Irish nonsense, sharpened to an arrow.

Moran can be heartfelt and ironic, genuine and putting it on. He demolishes nostalgia in a few choice words, and then summons up a bygone world where men smoked pipes and women cried at their dressing tables, a world where everyone knew what adulthood consisted of. It’s absurd. He doesn’t mean it. He kind of means it.

“I alone am entirely honest at all times,” he blusters, feckless yet exacting, reconciling us with the ridiculousness of who we are and how we fill our time. Seriously good fun.

To Dec 5. Box office 0844 4124658

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