THE NEXT TIME I LUNCHED with Bernard Buigues it was somewhat different: a couple of protein bars forced down amid the stink of kerosene aboard an old, soot-blackened Soviet-vintage Mi-8 helicopter. We were going mammoth-hunting.

We'd set out that morning from Khatanga, a town that I'd found bizarrely transformed by the presence of Buigues and his frozen beast. On a typical evening at its only restaurant and bar (called Restaurant Bar) you'd find a clientele that included TV producers from southern California, Dolgan tribesmen, suave Frenchmen drinking cognac toasts, and Russian mafiosi in black leather blazers, dancing stiffly with the mastodontic local prostitutes. (The bartender, meanwhile, would be watching television: a dubbed episode of Friends.)

Our group aboard the helicopter was almost as motley. Discovery Channel tech guys fussed with their expensive equipment like nannies with restless infants, while Buigues and another of the Frenchmen lolled back atop the reserve fuel tank, steeped in kerosene fumes, unconcernedly smoking Gitanes.

Below us in all directions stretched a howling desert of white, stubbled here and there with a few stunted larches leaning at crazy angles against the wind-borne snow. These miserable trees make up the most northerly forest in the world—and the spur of land they cling to, the Taimyr Peninsula, is the northernmost continental land on earth, riding high atop the hunched back of Mother Russia. It's a place farther east than Bangkok, farther north than Barrow, Alaska, and by the time I arrived, in mid-October, deep winter had set in for more than a month. Peering through the helicopter's porthole, I thought of Ice-Nine, the apocalyptic Cold War substance in Kurt Vonnegut's novel Cat's Cradle, one single drop of which is sufficient to freeze solid all the water on earth, forever.

But just as the Taimyr wilderness turns solid every September, in a single sudden shock, so too it thaws every June, abruptly, in a matter of just a few days. The barren ice fields become mosquito-ridden marshes, and the melting snow pours toward the Arctic Sea in streams and rivers that overflow their banks, cutting new channels through the hard substrata of frozen mud. This is when the mammoths come out. Not just mammoths, either, but other bizarre, antediluvian monsters: woolly rhinoceroses, giant elk, Pleistocene bison, all of which roamed these steppes until after the last Ice Age, 10,000 years ago—when all these shaggy beasts suddenly, mysteriously, died off.

The floods were what brought Buigues's first mammoth to light. A Dolgan herdsman named Ganady Jarkov stumbled upon it near a riverbank as he drove his herd of reindeer toward fresh grazing. He removed the tusks, which he later bartered to Buigues for some coffee, tea, and gasoline.

Thanks to the infusion of cash from the Discovery Channel, Buigues relaunched his expedition on an even grander scale last summer. Not only did he prepare to defrost the Jarkov mammoth, he also sent scores of local operatives out looking for bones, tusks, and other remains. Buigues recruited various clans of Dolgan tribesmen (known as "brigades"), promising to reward them for any material brought back from their summer wanderings.

A few days before my arrival, word had come in through the grapevine to Buigues's headquarters in Khatanga that the last of the Dolgan brigades was on its way back across the tundra, returning with a hefty load of bones and tusks. So we had gone out by helicopter to search for them, with nothing but the vaguest sense of possible rendezvous sites. The Taimyr Peninsula is almost the size of California, with an average of just one inhabitant every 13 square miles. It's easy to lose yourself there.