EDDIE IZZARD emerged from the pages of a giant book to show that he had discovered reading. There is no such unexpected revelation in Lee Evans's grand entrance at the start of his marathon West End run. His name in lights above the Lyric Theatre stage, Evans slowly descends a large staircase and, without wanting to reveal too much, it would probably be fair to relate that he doesn't quite make it to the bottom unscathed. Evans's act is built around a highly skilled celebration of incapacity, so a first night ought to be meat and drink to him: the higher the stakes, the more piquant the pratfall.

Because nerves, and their evil big brother, fear, are a constant factor in what Lee Evans does, it takes a while to realise that things are actually going really badly for him. Physically, he is assured as ever - swinging round the stage like a crazed Barbary ape - but the verbal sections of Evans's act are always slightly shakier. In the first 20 minutes tonight he swallows punchlines as a hungry man might devour digestive biscuits. And when your punchlines are of the quality of "What about this alcohol- free lager, eh, what is the point of that?", there is no margin for error.

By the end of an interminable plate-spinning routine, which, by its author's pained but pertinent admission, "needs a bit of work", there is an uncomfortably heartfelt air about Evans's relentless self-deprecation. But though he cultivates the hapless air of a pheasant in fame's headlights, this man has the sturdy heart of a true professional. It is this quality - allied with ferociously astute management - which ensures that each time Ev- ans seems to have got as far as it is possible to go, he goes one step further: from Perrier Award to TV series to film star. What's next? Perhaps the least attainable of all objectives for a British comic: to make more than five people in the US know who he is.

The programme contains a copy of a rejection letter from Opportunity Knocks, which, as starting at the bottom goes, just about takes the cake. Evans's awareness that the bottom can call again at any moment is - if anti-scatological pun laws will permit - fundamental to his act: hence the abundance of bodily functions. His comedy is the product of a harsh Thatcherite world; a world entirely without safety nets. Watching him simultaneously plummet into the abyss on stage and soar ever skywards in career terms is strangely reassuring.

Tonight, as usual, Lee Evans somehow carries it off. He does this by using his pain in his work: conveying to great comic effect the horror of a dog emerging from the anaesthetic after castration, or the agony felt by baked beans in a motorway service-station canteen ("Please Don't Leave Me Here!"). When a latecomer takes his seat in the first row - a one-way ticket to humiliation in front of any other vaguely competent comedian - the response to Evans's polite inquiry as to the reason for his tardiness is roughly along the lines of "What's it to you?" Evans's smile at this is so genuine everyone can share in it.

There's a funny (in both senses) moment near the end, when Evans observes that the butts of his jokes - bystanders and burger-eaters and toilet- sweepers - are "always the same guy". He pauses. "And that was me once."

What is so frightening, and at the same time so appealing, about this man is that he might be the last person in Britain to be completely devoid of irony. When Lee Evans thanks the assembled media vultures for "taking the time to come down", he actually seems to mean it.

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