Them Adventures with Extremists by Jon Ronson. Picador: £16 . Our rulers are really giant lizards masquerading as men and that's only one of the great conspiracy theories floating around. Stephen Dodd on shady goings on in the woods

THE Ku Klux Klan is having a makeover for the cameras, at least. Out go the old hatreds. In their place come personality workshops; repositioning in the political spectrum; the New Klan. Journalist Jon Ronson, who is Jewish, watches as old and new reach utter bewilderment at a traditional Cross-Burning ritual.

In days gone by, the Klan's fiery cross would have struck terror. Now, old certainties are replaced by ineptitude.

"I know that sometimes people have called it a Cross Burning," announces the Klan's "liberalising" leader Thom Robb, "but we know it to be a Cross Lighting."

The heavy crucifix, swathed in rags, lies on the ground, surrounded by puzzled white supremacists.

"Do we raise it and then soak it," asks one, "or soak it and then raise it?"

"In the past it's always been soaked and then raised," comes the reply.

"But if we soak it before we raise it, we'll get kerosene all over our hands and our clothes when we raise it."

Thom Robb, the Klan's high priest, intervenes.

"You can't raise it before you soak it," he says irritably. "How you going to soak it after you've raised it?"

From the ensuing silence, a quiet voice pipes up.

"We thought you'd have a ladder."

There is something chillingly endearing about the strange identity parade of fanatics, conspiracy theorists and the undeniably unhinged that peoples the pages of Ronson's Them. This is reportage from a fringe so distant that it seems to short-circuit reason. Logic, in these far-flung outposts of irrationality, follows rules unsuspected by the rest of us. This is a new common sense, defending itself from within a theoretical stockade lost in the hills, with a smoking AK-47 assault rifle for supporting argument.

RONSON set off with a brief. He would interview the fundamentalists of the world, from racists and bigots to men of rare or rabid faith. He introduced himself, moved within their circles, witnessed the public soundbites and the private slips. He was there when Islamic militants swore holy war; there when the mask fell away and the mastermind of the New, Kuddly Klan abused "faggot slime" through a public address system.

Ronson's is a strange and perplexing journey, with so many strange sights to see that one longs for a conclusion, for an author's definitive denial. It is not there. At its close, no-one says: "Don't worry, these things are fantasies, they could never happen in a street near you." Which is as it should be, for the truth seems to be that They are both potential prophets and the dumbest of dupes.

The central thread of Ronson's wholly entertaining investigations is that each extremist quaffs from a common punchbowl of ideas. Thus, each believes the world is being run by a shadowy elite. Each believes the elite meets secretly once a year to seed its dastardly plans.

But eccentricity, it seems, is as accommodating as religion, and to this potent cocktail each fanatic adds his own twist of lime. Thus, the Klansman holds that it is a Jewish conspiracy which wields ultimate power. Others point the finger at the Bilderberg Group, a true-life cabal of powerful industrial and political figures. Ronson meets arch conspiracy theorist David Icke, the former sportscaster who controversially - announced he was the Son of God. Icke's theory is that our secret rulers are giant lizards, masquerading as men.

WITH AN early April publication date, the suspicious reader might wonder whether a measure of leg-pulling is going on, but a rapid Internet check suggests Ronson has merely tapped a wide spectrum of extremism. The Bilderberg Group earns the attention of dozens of conspiracy-minded web-sites, and Icke's distrust of lizards is clear on his own site, where our reptilian foes are further categorised into specific species.

This is an investigation where comedy is married to a stomach-churning potential for violence. It is the source matter for countless X-Files, an array of modern myths and misgivings about the Waco siege, gun control, religious conviction (Ian Paisley makes an ebullient appearance) and shady goings-on in the woods.

Narrative leaps from Pythonesque humour to grim bigotry. A Klansman offers washing guidance to a comrade (never, ever, put your white robes of hate into a spin cycle with red laundry). A page away, a rival Klanner offers his own, unreconstructed version of Klan image.

"If I want to say nigger, I'll say nigger," threatens Jeff Berry. Apparently Jeff is the Klansman of choice for appearances on The Jerry Springer Show.

Ronson weaves his tale like a master, shuffling foolery (CEOs and world leaders paying homage to the effigy of an owl) with potentially worrying fact. He even tracks down the Bilderberg Group, through one of its founders, Denis Healey.

"To say we were striving for a one world government is exaggerated but not wholly unfair," Healey tell him. "Bilderberg is a way of bringing together politicians, industrialists, financiers and journalists."

Ronson asks him: "Does going help your career?"

"Oh yes," Denis replies. "Your new understanding of the world will certainly help your career."

Sounds a bit like conspiracy, then, wonders Ronson?

"Crap!"

Healey explodes.

"Idiocy! Crap! I've never heard such crap! That isn't a conspiracy. That is the way things are done. That is the world."

IT IS intriguing, nevertheless, that so little has been written about a group that brings together American presidents, British leaders and world financiers for informal talks about global policy. In an era when western politics are increasingly following the same free-market course, when the same enemies are identified and the same profit ideologies pursued, can it all be put down to coincidence and common sense?

In any event, Jon Ronson has proved, with an often hilarious account that does to world domination what Bill Bryson has done so exhaustively to travel, that Picador is no part of the shadowy New World Order. Unless it is all a counter-plot, of course, designed by Bilderbergers, orchestrated by political fanatics, and executed by looming man-lizards with the gift of the gab.