Eddie Izzard, Lyric, Shaftesbury Avenue, London

The feat of endurance is one thing, the feat of imagination is quite another. But this is Eddie Izzard we are talking about, the supreme exponent of mind-expanding nonsense, and his new one-man show, which has just started a 20-night run in the West End, takes his audience on an unforgettable journey. When it's all over, life is somehow not quite the same.

It's a relief to be able to say this, because with his straight-acting interests, Izzard hasn't done any comedy for five years, and hasn't had a West End show for 12. That's a long time to put your comic genius on hold, and those attending the first night last week could have been forgiven for wondering if the magic would still be intact. But from the moment Izzard took the stage, cutting something of a Restoration figure in jeans and tailcoat, it was like he had never been away. With Izzard there are no jokes and no punch lines, just a stream-of-consciousness monologue in which he applies a child's logic to some of mankind's biggest, and smallest, questions. It's an extraordinary high-wire act, unscripted, and the feeling that Izzard begins sentences without really knowing how they will end gives the show a marvellous tension. He is the classic Fool – turning total ignorance into the profoundest wisdom, seeing only the surreal in reality. And he had a largely sure instinct for that moment when a particular flight of fancy might just be overstaying its welcome. Only when he turned his attention to the hackneyed topic of Sarah Palin did the show temporarily lose its lustre.

Much of Stripped comprised a debunking of religion, but so lacking was Izzard in any aggressive intent that those upset by Richard Dawkins could not possibly have taken offence. Other concerns included dinosaurs, Noah's Ark, Wikipedia, the appendix, and why there are no films about farming, all somehow connected to each other.

Weavers – like those who created the Bayeux Tapestry – were the paparazzi of their day. "Anne Boleyn! Big wave, darling!" A plague of frogs is not a plague – "it's just a lot of frogs". The word assassins comes from hashish, he told us, before proceeding to act out a drug-befuddled attempt at a "hit". Even funnier was a sequence in which a messenger struggles to get out the news that Hannibal's army is approaching, such is the Latin language's dependence on endings. A wonderful night of warmth and silliness.