When I first heard about this book, the publicity spin on it suggested that it was going to be little more than a tiresome rip-off; ooh, the chimpanzee who starred in the Tarzan movies has - ho ho! - written a book! I didn't even bother filing this away under "books that should not be".

And then I was sent the hardback, and urged by a colleague to read it. And since then, I have been urging it on anyone who has cared to listen, for it is by some margin the most audacious, funny and even moving novel that I have come across in years.

The conceit is, it is true, that Cheeta the Chimp has written his Hollywood memoirs. But, after a throat-clearing "Note to the Reader" that is much funnier once you have read the book than before, you soon realise that the extraordinary nature of this autobiography extends beyond the premise that it was written by a chimpanzee. We begin in the grounds of a country house in England, where Rex Harrison, his wife Rachel Roberts and Dickie Attenborough are taking a break from filming "Fox's disastrous megaflop Doctor Dolittle", and taking bets on whether Cheeta will be able to get down from a monkey-puzzle tree. "Why don't we forget the money?" asks Rex of his wife. "If the monkey makes it you can sleep with Burton, if he'll have you, and if it doesn't, then I can divorce you but you have to promise not to kill yourself." A couple of pages further on, and Cheeta is describing Harrison as "universally despised, impotent, alcoholic, cruel, vain, brittle, snobbish and mephitic but still, under that carapace of protective acerbity, [a] very gentle and insecure human being".

This, then, is an alternative take on Hollywood's golden age; the place where, as Cheeta describes it, the actors perform dreams which are soaked up by the public watching them being played out on the screen. And the price of this is that the "dreamers", as Cheeta sometimes calls the stars, lose their minds. Cheeta works the grimmest parts of the fairytale even into his similes: "But that was as foolish a dream as Lana Turner's daughter Cheryl's hope that her stepfather Lex Barker would stop raping her." There is plenty more near or even past the knuckle like that, and James Lever knows how funny this can be when he writes "Chapter 8 has been removed on legal advice", yet allows us some clue, in the index, of what the chapter might have consisted of: look under "Williams, Esther" - "nauseatingly self-justifying autobiography of, 225", and so on.

But this is far more than a wicked spoof tell-all. It operates, and works smoothly and well, on several levels: it is a Swiftian satire, as Cheeta walks through the world observing human foibles and, often as not, getting them exactly wrong, as when he imagines that the stuffed animal heads adorning the walls of one actor's house are all old pets, lovingly preserved. It is a textbook example of the unreliable narrator ("Incidentally, during this conversation, Marlene [Dietrich] and Mercedes [de Acosta] were stimulating each other's sexual organs. You can well imagine how bored I was watching them ..."). It is also deeply funny. The story of what happens when Johnny Weissmuller and David Niven borrow Douglas Fairbanks's Rolls-Royce, and rig it up so it looks as if Cheeta and Jackie the MGM lion are driving it, will have you laughing out loud for 10 pages.

But it is also a love letter to Weissmuller, the original star of the Tarzan films; a tribute that bursts its own narrative confines, and stands the novel on its head, to become a hymn to a certain kind of beauty and innocence. Weissmuller is as much the star of the book as Cheeta.

And the prose ... well, no wonder people were wondering whether Will Self or Martin Amis were behind the pseudonym (only revealed some time after publication. There are signs, incidentally, that Lever has read, and tried not to overlap with, Self's splendid Great Apes). The prose is impeccable - supple, intelligent, penetrating, vigorous. A delight to read. Lever couldn't have got away with this without it.