First the good news: Eddie Izzard has reclaimed his crown as the most poised comedian in Britain. There was a time, earlier this decade, when the cross-dressing comedian from Bexhill had turned into a parody of himself, mainlining on ahs and oohs while running dry on the glorious imaginings that fuelled his first flush of success.

Now, starting a West End run that sold out in seconds, Izzard is trim and focused once again. Supremely relaxed in his tails and jeans, he has the great performer’s way of making time itself bend to his wishes. He makes being funny for a roomful strangers look so natural that you wonder why we don’t all do it.

And the bad news? Well, if you’re one of the opening-night punters who clearly adored Izzard’s suave deconstructions of religion, ancient history and the natural world, I daresay there is none. For me, though, Izzard’s delicious delivery keeps promising an element of human contact that rarely arrives.

Oh, he’s all for humanity – proposing a vague humanism and a gentlemanly radicalism: “People inside the room,” he chirps, “we’ve got to chaaange things!” But in all his jolly musings on the wonder of Wikipedia, the silliness of nature – four stomachs? In a cow? How can that be necessary? – and his enjoyable transpositions of modern mores on to Ancient Man, everything remains notional.

His only characters are historical – Hitler, Noah, Darwin. He talks about the fallacy of believing in God with the same genially miffed air in which he talks about waiting for software updates on his computer. Given that half of the comedians in Britain seem to have been plying the same sub-Dawkinsy diatribes in the past few years, this is a case of preaching atheism to the already unconverted.

In America, where this show started, taking the rise out of Bible stories is an edgier proposition. Here, big deal. The religious and unreligious alike can enjoy his demolition job on the Noah’s Ark story: it’s not as if, as Izzard suggests, that God wrote the Old Testament himself.

Compare his attitude with the Irish comic Dylan Moran’s much more sophisticated take on it on his present tour, which takes godlessness as a given, then asks how we fill that gap. So why go on so about God’s unfairness? God, Izzard tells us, killed his mother too soon and Hitler too late – but that’s the sole glimpse he gives of any interior rage that might be motoring his act.

We’re left, though, with some moments of pure Izzardian delight – a superb set piece about the finickitiness of Latin; a brief but brilliant depiction of life on inhospitable Mercury, digs at cake mix and BlackBerries and the Roman Empire. It plays like the observations of a stupendously creative man seeing the world primarily through the internet, through books and films and gadgets. It’s charming, it’s charismatic, it’s accomplished. But it lacks bite.

To December 23. Box office: 0870 0400081 (returns only)

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