TELEVISION REVIEW;

By NED MARTEL
Published: January 14, 2005

here are bound to be creatures in the ocean depths that human eyes have never encountered, or microbial beings with intricacies as yet unexplained. When it comes to mammals, however, the beast deemed most elusive is the snow leopard, which prowls the ''highest, most hostile of mountain ranges.''

That Himalayan description comes from Hugh Miles, a sage naturalist who narrates and leads the expedition in this Zen-like, meditative installment of ''Nature,'' which is being shown on Sunday night on PBS. The endangered snow leopard is sometimes stalked by poachers, who prize its pelt and bones, but the 5,000 remaining are now pursued mainly by shutterbugs. ''Nature'' filmmakers deploy hidden cameras with high hopes of detecting the feline prowling silent, windswept trails.

''Now we have to wait for the pussycats,'' one photographer says, as Mr. Miles and his deputy, Mitchell Kelly, set up video units that any motion will trigger. Of course, herders and yaks stroll by, so there are many frames of mundane life at 15,000 feet in northern India. But eventually a hoped-for prowler arrives and marks a rocky tower with his scent.

The cameras are faulty on occasion, but mostly ingenious, and they allow intimate details of an animal whose motion truly suggests poetry. It is easy to see why the fierce, tufted gray beast inspired writers like Peter Matthiessen, who followed the mythic hunter on a spiritual journey.

The show's cameramen wax a little poetic themselves, as Mr. Kelly muses, ''They say a leopard never changes its spots, but snow leopards do.'' He means that such spots come and go in the furry folds as the cat undertakes coiled poses and slinky strides down the rock face. Eventually, over four years and long, silent waits in subzero climes, these men memorize the looks and habits of five resident cats and three transient interlopers. There are telltale markings: a twist of one male's long Tigger-like kinked tail, the scratches on the face of a scrappy survivor, a forlorn female howling from a ridgetop for some companionship.

That come-hither song goes against the snow-leopard profile. Traveling solo along dangerous trails, the animals rub their cheeks on a marked rock and spray it with urine, with a foreboding scent that lasts for days. In the warmer months of mating season, however, that same aroma from the female changes meaning: ''Stay away'' becomes ''you're welcome to approach,'' the narrator says.

One local male accepts the Mae West invitation. The video voyeurs keep a semirespectful distance, editing the amorous exchange to just a twitch of the hips and a spinal shudder. Then the filmmakers pray for the chance to see some resulting cubs, if their patience is rewarded.

There are limits to how much a human can take in this environment, and Mr. Kelly explores these boundaries. He identifies with the snow leopards as they stumble on loose rocks and snowy bluffs, and notes that they too get winded in the high altitudes. But all Mr. Kelly's strenuous conditioning doesn't protect him from the elements, and he starts to gasp, then vomit, hallucinate and black out, suffering from acute altitude sickness with some goals unmet. Sherpas and a yak with a sturdy back come to his rescue.

I won't reveal which moments these pioneering cameras have yet to capture because the thrill of this wildlife pursuit is in experiencing the filmmakers' surprise at their success and then their setting of higher goals. One priceless moment comes when Mr. Kelly marks a camera with his own scent and a leopard responds with a swipe at the camera and a sniff that fogs the lens but speeds the viewer's heart rate. No one is in danger, but this ''ultimate mountain killer'' can elicit fear even at safe distances.

This is not some dopey documentary for those who want to see Garfield's cousins act like merry pranksters, and it's a cut above ''Wild Kingdom'' episodes, in which a fanged predator fells some feckless gazelle. Carnage occurs, but the cats exhibit such a mesmerizing wildness that you can't stop watching the intricate mechanics of their movements, even if, like Garbo, they want to be alone.