Narrator: IN AN ANCIENT RUSSIAN FOREST, WHERE LITTLE LIFE SEEMS TO STIR, ONE MAN FILMED ITS MOST FABLED RESIDENT FOR THE FIRST TIME -- THE WILD SIBERIAN TIGER.

IT'S AN ACHIEVEMENT THAT TOOK YEARS OF WATCHING AND WAITING WHILE LIVING IN A HOLE IN THE GROUND FOR MONTHS AT A TIME.

THERE MUST HAVE BEEN TIMES WHEN HE WAS ON THE EDGE OF INSANITY, I'M SURE.

HIS STORY IS ONE OF ENDURANCE AND ISOLATION.

BUT THE RETURN ON THIS HARDSHIP IS HIS UNPARALLELED FOOTAGE OF THREE GENERATIONS OF A TIGER FAMILY.

NOW I'M EMBARKING ON MY OWN TIGER ODYSSEY WITH THIS REMARKABLE MAN AS MY MENTOR.

THE JOURNEY ISN'T WITHOUT RISKS... [ BANG ] GUNSHOT.

BUT DISCOVERY IS ITS OWN REWARD... YOU'RE NOT GOING TO BELIEVE THIS.

AT THE FAR EDGE OF RUSSIA'S WILDERNESS.

Narrator: IN 2005, KOREAN FILMMAKER SOOYONG PARK EMERGED FROM RUSSIA'S FROZEN FORESTS, THE FIRST MAN TO FILM FAMILIES OF SIBERIAN TIGERS IN THE WILD.

HE WENT THROUGH YEARS OF LONELINESS AND DANGER, STALKING A PREDATOR, ONE OF THE RAREST CATS ON EARTH.

PARK WAS PREPARED TO INVEST MORE OF HIS LIFE THAN ANYONE BEFORE HIM.

HE CAPTURED FOOTAGE OF THE ANIMALS THAT HAUNTED THE SEEMINGLY EMPTY FOREST.

PARK LEARNED TO UNCOVER THE TIGERS, NOT FABLED WHITE, BUT CAMOUFLAGED BY COATS THE COLOR OF FLAMES.

HIS LEGACY IS A UNIQUE RECORD OF OVER 1,000 HOURS OF TIGER LIFE.

A LAND OF BEARS AND POACHERS -- A LAWLESS FRONTIER AND TIGER COUNTRY.

THE RUSSIAN FAR EAST...

IT FEELS LIKE THE EDGE OF THE WORLD.

I'M CHRIS MORGAN, AN ECOLOGIST.

I'VE COME TO A UNIQUE PART OF THIS VAST WILDERNESS.

I'M HERE TO UNCOVER AN AMAZING STORY OF ENDURANCE AND ISOLATION IN A HIDDEN CORNER OF RUSSIA.

I LIVE AND WORK IN THE USA.

THERE WE HAVE MANY OF THE ANIMALS IN THESE FORESTS, LIKE BEARS AND WOLVES.

ONLY HERE, IN THIS PART OF RUSSIA, THEY ROAM THE SAME WOODS AS TIGERS AND LEOPARDS.

THE TIGERS HERE ARE REALLY HARD TO SEE.

THEY ROAM GREAT DISTANCES -- UP TO TEN TIMES FURTHER THAN THEIR TROPICAL COUSINS, BECAUSE PREY, LIKE DEER AND WILD BOAR, ARE FEW AND FAR BETWEEN.

EVERYTHING IS NERVOUS, FROM BIRDS TO PEOPLE -- ALL POTENTIAL TIGER PREY.

THIS FOREST FEELS MAGICAL, FULL OF EXTRAORDINARY SIGHTS LIKE THESE GIANT NESTS OF BROKEN BRANCHES.

I'VE SEEN A FEW OF THESE IN THE FOREST, AND WHEN YOU INITIALLY LOOK AT THEM YOU THINK THAT THEY'RE BIRDS' NESTS, BUT THESE ARE ACTUALLY BEAR NESTS.

BACK IN THE U.S., THE BLACK BEARS I STUDY ARE THE TOP OF THE FOOD CHAIN.

WHEN THERE ARE TIGERS IN THE WOODS, BEARS ARE ON THE MENU.

I'M ONLY SPENDING A FEW WEEKS HERE -- PARK STAYED FOR MONTHS AT A TIME.

I HAVE BEEN WARNED I MAY NEVER SEE A TIGER.

I NEED SOMEWHERE TO SET UP A HIDE.

WE'VE BUILT THIS TREE STAND, AND I'M GOING TO TRY AND SPEND SOME TIME UP HERE AND REALLY GET A SENSE OF WHAT PARK WENT THROUGH WHEN HE SPENT ALL THOSE CONSECUTIVE MONTHS LOOKING AND WAITING FOR TIGERS TO APPEAR.

I THINK IT'S QUITE A BIT BIGGER THAN THE ONE THAT HE USED, BUT WE'VE PICKED A NICE SPOT OVERLOOKING THIS FROZEN RIVERBED.

[ LAUGHS ] IT'S BIG.

THE PLATFORM DOESN'T OFFER MUCH PROTECTION, BUT MIGHT KEEP ME OUT OF HARM'S WAY.

THE NIGHT BELONGS TO OTHERS... [ ANIMAL HOWLING ] WOLVES, BEARS, AND TIGERS.

MY WHOLE MOTIVATION FOR BEING HERE IS I LOVE LARGE CARNIVORES.

AND I LOVE THINKING ABOUT THEIR WILD LIVES AND WHAT THEY NEED.

AND IN A FOREST LIKE THIS, THERE IS NOTHING MORE EXTREME.

MOST OF MY TIME I SPEND STUDYING BEARS, BUT ALSO A LITTLE BIT OF WOLVES AND A LITTLE BIT OF COUGARS.

SO I KNOW MY NORTH AMERICAN CARNIVORES, BUT THAT'S WHERE THE SIMILARITIES END -- THIS FOREST HAS ALL KINDS OF INCREDIBLY EXOTIC SPECIES IN IT, INCLUDING THE TIGER.

AND THAT'S WHERE I'M OUT OF MY ELEMENT A LITTLE BIT, BUT I LOVE THAT.

TO SUCCEED WHERE ALL OTHERS FAILED, SOOYONG PARK WENT TO NEW EXTREMES.

THE EVIDENCE IS IN HIS FOOTAGE.

HE LEFT HIS WIFE AND CHILDREN IN KOREA AND DUG A FOUR-FOOT HOLE IN THE GROUND.

OVER FIVE YEARS, HE WAITED AND WATCHED, STAYING INSIDE FOR MONTHS -- HE NEVER LEFT EVEN TO GO TO THE BATHROOM.

THE TIGERS WOULD REVEAL THEMSELVES BRIEFLY, THEN DISAPPEAR.

AGAIN HE WOULD WAIT, AND WAIT.

EVENTUALLY, HE CAUGHT THE UNSEEN LIFE IN THESE BARREN FORESTS --- HE FILMED LYNX... SABLES... WOODPECKERS... AND RACCOON DOGS.

BUT IT IS HIS INTIMATE IMAGES OF TIGERS THAT ARE UNIQUE.

HE DIDN'T JUST GRAB ODD SHOTS.

HE GOT TO KNOW INDIVIDUALS AND THEIR FAMILIES.

HE GAVE THEM NAMES FROM FAIRYTALES -- SNOW WHITE, HANSEL AND GRETEL.

HIS CAMERAS WERE PRIMITIVE.

BUT HIS FOOTAGE OF A MOTHER AND CUBS JUST INCHES AWAY IS UNPARALLELED.

I UNDERSTAND WHY ANYONE MIGHT DEDICATE THEIR LIFE TO ANIMALS, BUT PARK TOOK IT TO ASTONISHING LIMITS.

ONE OF THE MOST IMPRESSIVE THINGS ABOUT PARK IS NOT JUST THE FACT THAT HE WOULD SIT FOR MONTHS IN A HIDE ON HIS OWN WAITING FOR TIGERS TO COME BY, BUT THAT HE WOULD SIT SOMETIMES FOR MONTHS BEFORE THE FIRST TIGER EVEN SHOWED UP.

THERE MUST HAVE BEEN TIMES WHEN HE WAS ON THE EDGE OF INSANITY, I'M SURE.

ANY HUMAN WOULD BE.

I THOUGHT I HAD SEEN TIGERS IN THE SNOW ON FILM BEFORE, BUT THE TRUTH IS THEY WERE ALMOST CERTAINLY FILMED IN CAPTIVITY.

THERE ARE MORE TIGERS IN CAGES THAN THERE ARE LEFT IN THE WILD.

THE TIGERS IN THE YARD OF THIS RUSSIAN HOME, HAVE BEEN FILMED COUNTLESS TIMES -- TIGERS FOR HIRE FOR A FEW HUNDRED DOLLARS A DAY.

THESE ARE SHADOWS OF THEIR WILD BROTHERS, BUT TIGERS ARE STILL AWESOME PREDATORS.

SOME OF THESE CATS EAT BEARS FOR A LIVING -- PRETTY DARNED IMPRESSIVE CARNIVORES.

I'VE COME TO FIND OUT WHY IT'S SO HARD TO SEE THEM IN THEIR NATURAL HABITAT.

YOU'D THINK THAT AN ORANGE CAT LIKE THAT WOULD STAND OUT LIKE A SORE THUMB ON THIS WHITE BACKDROP, BUT THEN YOU SEE THESE ORANGE LEAVES THAT ARE ALL PARTLY ON THE TREES AND MOSTLY ON THE GROUND, AND IT JUST BLENDS IN PERFECTLY.

INCREDIBLE.

UNEXPECTED, ACTUALLY.

PARK NEVER CAME TO THIS ODD ENCLOSURE AT THE EDGE OF THE WOODS.

HE FILMED IN THE WILD.

MAKES ME APPRECIATE HIS WORK EVEN MORE.

SIBERIAN TIGERS' TERRITORIES ARE VAST.

THEY CAN COVER OVER 1,000 MILES.

THE TERRAIN IS TOUGH.

WHERE WOULD I BEGIN TO LOOK?

LUCKILY I HAVE THE PERFECT GUIDE...

SO, PARK.

AH!

Morgan: PARK HIMSELF.

CHRIS MORGAN.

PARK.

[ SPEAKING KOREAN ] NICE TO MEET YOU.

Morgan: GOOD TO MEET YOU TOO, YEAH.

HE WILL BE MY MENTOR FOR A SHORT TIME.

WHEN HE LEAVES, I'LL LOOK FOR TIGERS BY MYSELF.

WE'RE HEADING BACK TO THE FORESTS WHERE PARK WORKED, TO THE WOODS HE CALLED HOME FOR OVER FIVE YEARS.

PARK'S PREPARATION FOR A LIFE IN THE WILD IS UNCONVENTIONAL -- UNTIL 17 YEARS AGO, HE STUDIED LITERATURE.

THEN KOREAN EDUCATIONAL TV SENT HIM TO THE RUSSIAN FAR EAST.

PARK IS COMING BACK TO SHARE HIS STORY.

WHAT DO YOU THINK?

OH, MY GOD.

BIG?

IS IT?

BIGGER THAN YOURS?

I KNOW, I KNOW.

BUT I THINK IT WILL BE GOOD, IT'S QUITE CAMOUFLAGED.

WHEN YOU WERE IN YOUR HIDE, WHAT DID YOU EAT?

300 BAGS OF RICE?

AND THAT WAS IT, THIS IS ALL YOU ATE?

A TOILET?

OKAY, THAT WAS MY NEXT QUESTION.

WHAT DO YOU DO FOR A TOILET?

[ BOTH LAUGHING ] I'M SO INTRIGUED.

YEAH, PAPER.

YES, PLASTIC BAGS.

YEAH, HOPEFULLY NOT THE ONE WITH THE NUTS IN IT.

WHAT WAS THE TEMPERATURE, WHAT WAS IT LIKE?

MINUS 30?

WOW.

THAT'S BEYOND WHAT I CAN COMPREHEND, ACTUALLY -- EVERYTHING, THE BASIC FOOD, THE TEMPERATURE, THE PATIENCE, THE ENDLESS WEEKS.

IT'S ALMOST UNBELIEVABLE.

AT THESE TEMPERATURES, YOUR EYELIDS CAN FREEZE SHUT IN YOUR SLEEP.

PARK ENDURED THESE DEBILITATING TEMPERATURES FOR MONTHS, WITHOUT LEAVING HIS FOUR-FOOT WORLD.

WHEN HE EMERGED, HIS MUSCLES HAD WASTED -- HE COULD BARELY WALK.

PARK DOESN'T JUST THINK MY PLATFORM IS TOO BIG -- HE'S NOT SURE IT'S IN THE RIGHT PLACE, EITHER.

LIKE PARK, BEFORE HE PICKED HIS HIDING SPOTS, I HAVE TO BE CERTAIN TIGERS ARE IN THE AREA... AH, YES!

Morgan: I KNOW HOW TO TRACK PREDATORS.

BACK IN THE U.S., I AM REGULARLY ON THE TRAIL OF BEARS AND WOLVES.

FINDING SIGNS OF TIGERS IS DIFFERENT, THE FACTS ARE STARK -- ONLY 400 SIBERIAN TIGERS IN AN AREA THE SIZE OF MY HOME STATE OF WASHINGTON.

20 TO 30 OF THEM POACHED EVERY YEAR, WORTH $50,000 DEAD -- IF YOU CAN FIND ONE.

PARK IS GOING TO SHOW ME HOW.

CAN YOU SMELL IT?

OH DEFINITELY, DEFINITELY CAT SMELL!

OH LOOK HERE, IS THAT A HAIR?

WHAT DO YOU THINK?

YOU THINK IT'S TIGER?

HAIRS.

TO FIND THE TIGERS, PARK HAD TO THINK LIKE ONE -- A SKILL I WILL NEED.

THERE'S A LOT TO LEARN.

HE STARTS TO SHARE HIS SECRETS.

BUT THOSE ARE NOT MOUSE HAIRS.

PARK TAUGHT HIMSELF TO BE AN EXPERT ON THE ELUSIVE CATS AND TO SHARE THEIR WORLD.

[ POUNDING ] [ GUNSHOT ] GUNSHOT.

SHOTGUN -- SOMEBODY KILL... Morgan: WE ARE NOT ALONE.

WE NEED TO STAY OUT OF SIGHT.

RUNNING INTO ARMED POACHERS OUT HERE COULD BE FATAL.

PARK NEEDED TO STAY HIDDEN FROM TIGERS AND THE MEN HUNTING THEM.

THEY SELL THEM ON THE BLACK MARKET IN NEIGHBORING CHINA AS TRADITIONAL MEDICINE.

TIGERS HAVE BEEN HUNTED TO THE BRINK OF EXTINCTION.

THE FEW CATS THAT REMAIN STAY AS FAR FROM PEOPLE AS THEY CAN.

OH, OH!

[ LAUGHING ] TIGER TRACKS!

OH!

THAT IS UNBELIEVABLE.

I CAN'T BELIEVE WE FOUND THEM.

I HAVE DREAMT OF SEEING EVEN A TRACK SINCE I WAS A CHILD.

AND THIS IS...

SO IT'S QUITE AN EMOTIONAL MOMENT.

IT'S, UH...

THESE ARE OLD TRACKS, BUT LOOK AT THESE, SEE THE TOES HERE?

I'M DYING TO PLACE MY HAND INTO THE TRACK OF A TIGER.

WHAT DO YOU THINK, HOW MANY DAYS?

THREE OR FOUR DAYS OLD?

THAT SEEMS FRESH ENOUGH TO ME.

IT'S SUCH A SPIRIT BOOSTER.

THAT'S INCREDIBLE FOR ME THAT YOU KNOW THE HISTORY OF POTENTIALLY WHO THIS INDIVIDUAL CAT IS.

LET'S LOOK FURTHER UP HERE, I WANT TO SEE IF THERE'S MORE.

THE TRACKS MIGHT BE FROM A TIGER PARK FILMED AS A CUB.

HE NAMED HER GRETEL.

I WOULD LOVE TO FIND HER.

THIS FROZEN RIVERBED, COVERED WITH DEER TRACKS, IS A PERFECT SPOT FOR A REMOTE CAMERA.

DO YOU USUALLY PUT A GPS LOCATION ON YOUR CAMERAS?

OH, YOU JUST REMEMBERED.

PARK'S EQUIPMENT WAS BASIC, BUT IN SOME WAYS HE WAS AHEAD OF HIS TIME.

HE BUILT MOTION SENSORS TO TRIGGER HIS HIDDEN CAMERAS.

I USE THESE MODERN VERSIONS TO STUDY BEARS.

THIS PART OF SIBERIA IS HOME TO WEIRD AND WONDERFUL SPECIES THAT I WOULD LOVE TO SEE.

I AM GOING TO LEAVE THE CAMERAS OUT AND CHECK THEM IN A FEW WEEKS.

WHEN PARK HID HIS CAMERAS, EACH POSITION HAD BEEN CAREFULLY PLANNED.

HE FOUND THE VALLEYS WITH THE MOST PREY; HE FOLLOWED THE CALL OF THE CROWS, AND TRACKS IN SNOW; LOCAL HUNTERS SAY HE LEARNED TO READ THE WHITE BOOK.

EVENTUALLY, IT LED HIM TO THE TIGERS.

THE FIRST TIGER PARK ENCOUNTERED WAS AN ADULT MALE IN HIS PRIME.

PARK FOLLOWED CROWS TO A TIGER KILL.

HE HID CAMERAS AROUND IT, WHILE HE WATCHED AND FILMED FROM A HIDE.

EVEN THOUGH HE WAS ALONE, HE CAPTURED THE SCENE FROM SEVERAL ANGLES.

TEN FOOT, NOSE TO TAIL, AND WEIGHING UP TO A QUARTER OF A TON, FATHERING ALL THE CUBS IN THE AREA, THIS TIGER WAS THE DOMINANT MALE.

PARK CALLED HIM "KING BIG."

[ SNARLS ] YET EVEN KING BIG WAS CAUTIOUS -- SENSING THE CAMERAS WAS ENOUGH TO PUT HIM OFF.

PARK KNEW THE TIGER'S TERRITORY WAS SO LARGE HE MIGHT NOT RETURN FOR MONTHS.

KING BIG HAD GOOD REASON TO BE WARY.

POACHING IS RIFE -- WE'VE FOUND MORE TRACKS.

WE ARE NOT THE ONLY ONES ON THE TRAIL.

DO YOU THINK THE TIGER CAME FIRST AND THE MAN IS FOLLOWING HIM?

AND THEN THE MAN AFTERWARDS.

EASIEST WAY FROM A TO B FOR THE TIGERS.

YEAH, PERFECT.

I AM BEGINNING TO PICK UP THE TECHNIQUES PARK USED TO HOME IN ON HIS TIGERS.

NOW IS MY CHANCE TO VISIT THE TINY SPACE IN WHICH HE WAITED.

WOW, LOOK AT THAT -- HOME SWEET HOME, PARK.

OH, MY GOODNESS, THAT'S SO INTERESTING TO SEE IT!

OH, MY GOODNESS!

IT'S SMALL!

SO SMALL!

HOW LONG DID YOU STAY IN HERE?

SEVEN MONTHS.

RACCOON DOG?

TO FILM AT NIGHT, PARK ADAPTED INFRARED SECURITY CAMERAS.

HE HAD NEVER SEEN THE TIGER HE KNEW AS "BLOODY MARY," NAMED AFTER HER GRUESOME KILL SITES.

HE HAD TO WAIT 60 DAYS BEFORE HE FINALLY MET HER.

SHE WAS FOLLOWED BY THREE CUBS.

HAVING LEFT HIS WIFE AND CHILDREN IN KOREA, THIS IS WHERE PARK MET HIS SECOND FAMILY.

Martin: SKY WHITE?

OKAY.

HIS SECOND ENCOUNTER WITH THIS FAMILY WAS CHILLING.

PARK COWERED INSIDE AS BLOODY MARY AND HER CUBS ATTACKED.

THE PLANKS BROKE WITH THREE TIGERS ON THE ROOF.

ITS LEG IS DOWN HERE, AND YOU'RE SITTING... MY GOD.

[ LAUGHING ] AND YOUR HEART IS GOING...

THEY COULD HAVE KILLED HIM, BUT FOR SOME REASON BLOODY MARY LED HER TIGERS AWAY -- SHE LET PARK LIVE.

DID YOU SEE BLOODY MARY FROM THE -- THE LAST TIME YOU SAW BLOODY MARY?

Morgan: LIKE SOMETHING FROM A WAR ZONE, POACHERS HIDE GUNS IN THE UNDERGROWTH.

BLOODY MARY WAS KILLED WHEN SHE STEPPED ON A TRIP WIRE TRIGGERING A RIFLE.

SO, YOU SEE HER HERE WITH HER FAMILY, AND THEN THE LAST TIME YOU SEE HER IS WHEN SHE'S BEEN SHOT BY A POACHER'S RIFLE TRAP.

PARK SEEMS TO RE-LIVE HER TRAGEDY.

I REALLY WANT TO SEE A TIGER.

ONLY THREE MONTHS?

ONLY THREE MONTHS.

PARK'S DREAM WAS TO TELL THE STORY OF A WHOLE FAMILY.

NOW BLOODY MARY WAS DEAD, HIS HOPES RESTED ON HER THREE CUBS.

THEY WERE ALMOST FULLY GROWN, SO HE HOPED THEY WOULD SURVIVE ON THEIR OWN.

PARK FOLLOWED THEIR TRACKS, THROUGH THE RIVER VALLEYS AND FORESTS, OVER THE MOUNTAINS, ALL THE WAY TO THE COAST.

WE'RE GOING TO RETRACE SOME OF HIS ROUTE SO I CAN VISIT THE OTHER PLACES HE FILMED.

...AND SLEEP IN THE MOUNTAINS AND GO, GO.

Morgan: FROM THE MOUNTAINS TO THE COAST?

PARK LEADS ME TO THE FARTHEST BORDER OF THE TIGERS' DOMAIN -- THE PACIFIC OCEAN.

WOW.

THIS IS IT.

[ EXCLAIMING ] IT'S A DIFFERENT WORLD, AND EVEN LESS LIKE A PLACE I WOULD EXPECT TIGERS TO LIVE.

WE DON'T SEE MANY ANIMALS, BUT I AM FINDING EVIDENCE OF THEM NOW.

SIKA DEER CANNOT FIND VERY WELL.

NO, NO, NO.

WOOD CHIPS HERE.

DEER.

SMALL DEER, ARE THESE ROE DEER?

EVEN THE OCCASIONAL GLIMPSE...

OTTER!

OTTER!

THEY WANT THE NUTRIENTS AND SALT.

SO, THE TIGERS KNOW IT?

CHRIS!

AH, THAT'S TIGER IS IT?

OH, WOW, LOOK!

YES!

ON CUE -- PROOF OF TIGERS ON THE SHORE.

OLD, HUH?

OH, THAT'S AMAZING TO SEE THEM ON THE BEACH!

LOOK AT THE SIZE, VERY BIG DISTANCE, IT MUST BE A BIG TIGER, YEAH.

MAYBE A BIG MALE.

IT'S EXCITING, EVEN IF THESE TRACKS ARE OLDER THAN THE LAST ONES WE FOUND.

PARK'S SEARCH ALONG THE COAST FOR THE THREE CUBS PAID OFF.

HE FOUND TWO OF THEM LIVING TOGETHER, SHARING A KILL.

HE WAS CONCERNED THAT THE FEMALE CUB HE CALLED SNOW WHITE HAD DISAPPEARED.

WITH LUCK SHE HAD SIMPLY GONE IN SEARCH OF HER OWN TERRITORY, SOMEWHERE SAFER, PERHAPS.

THE REMAINING TWO TIGERS STAYED ON THE COASTAL EDGE OF THEIR MOTHER'S TERRITORY.

IT WAS UNUSUAL TO SEE SUCH LARGE CATS TOGETHER, BUT PARK INSISTS TIGERS ARE MUCH MORE SOCIAL THAN SOME SCIENTISTS SAY.

BEFORE LONG, THINGS CHANGED.

[ SNARLING ] THE MALE REFUSED TO SHARE HIS KILLS WITH HIS SISTER.

THE FAMILY WAS SPLITTING UP.

NOW, EACH TIGER WOULD NEED ITS OWN TERRITORY.

PARK CAREFULLY PLANNED NEW HIDES, EACH WITH A NETWORK OF REMOTE CAMERAS.

WOW!

YEAH, SO YOU COULD SEE FROM YOUR HIDE LOOKING THAT WAY TOWARDS WHERE THE CAMERA TRAPS WERE.

IT LOOKS LIKE GOOD TIGER HABITAT THERE, HEY?

YEP, THAT'S WHERE I WOULD BE IF I WAS A TIGER.

AFTER THEIR MOTHER'S DEATH, THE TWO TIGERS SPLIT HER COASTAL TERRITORY BETWEEN THEM.

THE EDGE OF THEIR RANGE WAS THE OCEAN.

PARK KNEW IF HE FOLLOWED THE COAST, HE WOULD FIND THE TIGERS PATROLLING THEIR PERIMETER.

HE CAPTURED THEM STALKING THE CLIFF TOP RIDGES, A POSTCARD IMAGE, FRAMED BY WILD AZALEAS.

PARK FILMED THE MALE TIGER, SKY WHITE, SURVEYING HIS TERRITORY FROM CLIFF TOP BLUFFS.

WE'VE COME TO THE SAME SPOT.

IT'S A MAGNIFICENT LOOKOUT POINT.

SHOTS OF A TIGER SCANNING THE PACIFIC COAST HAD NEVER BEEN SEEN BEFORE.

THIS IS INCREDIBLE, PARK.

THIS IS ONE OF MY FAVORITE PARTS OF YOUR FILM, WHERE THE TIGER COMES OUT AND LOOKS LEFT AND RIGHT AND ASSESSES HIS TERRITORY.

AND WHEN YOU WERE IN THE HIDE, HOW MANY DAYS WAS IT BEFORE THE TIGER ARRIVED?

[ MARTIN LAUGHS ] AND BEFORE 80 DAYS, DID YOU THINK, "FORGET IT"?

DID YOU SOMETIMES THINK, "FORGET IT, I CAN'T WAIT."

PARK KNEW HE WOULD FACE YEARS OF ISOLATION AND HARDSHIP.

BUT HE WAS UNPREPARED FOR HIS TIGERS' TRAGIC STRUGGLE FOR SURVIVAL.

PARK HOPED THE CUB, SKY WHITE, WOULD REPLACE HIS FATHER, KING BIG, AS THE DOMINANT MALE.

BUT LIKE HIS MOTHER BEFORE HIM, THE YOUNG MALE DIED BEFORE HIS TIME, MURDERED BY POACHERS.

THAT MUST BE VERY SAD FOR YOU TO THINK ABOUT THAT?

THE REMAINING TIGER ON THE COAST, THE SISTER, MOON WHITE, SURVIVED THROUGH TO THE NEXT YEAR.

HE PICKED UP HER TRAIL ON THE SAME COASTAL RIDGES.

SHE WAS MARKING HER TERRITORY AND PARK WAS DELIGHTED TO DISCOVER SHE WAS PREGNANT.

SHE LOOKED UNDERWEIGHT.

PARK KNEW HOW HARD IT IS FOR A FIRST-TIME MOTHER AND HER CUBS TO SURVIVE.

MONTHS LATER, HE WAS ABLE TO FILM HER WITH HER CUB.

THE WINTER HAD BEEN ESPECIALLY HARSH, AND PREY HAD PLUMMETED.

HE TRACKED THE MOTHER AND CUB TO A VILLAGE.

IN HER DESPERATION TO FEED THE CUB, SHE HAD TAKEN A DOG.

WHEN HE NEXT FOUND THE PAIR, THE CUB WAS IN TROUBLE.

HIS PAW WAS INJURED AND BADLY INFECTED.

MOON WHITE WAS EAGER TO MOVE ON IN SEARCH OF FOOD.

PARK WATCHED THE CUB FALLING FURTHER AND FURTHER BEHIND.

HE NEVER SAW EITHER OF THEM AGAIN.

YEARS IN THE WILD GAVE PARK AN UNDERSTANDING OF THE FRAGILE RELATIONSHIPS IN NATURE.

IN THIS PART OF SIBERIA, ONE SPECIES OF TREE SUSTAINS ALL LIFE.

IF THE PINE TREES FAIL TO FRUIT, DEER AND BOAR -- THE TIGERS' PREY -- MUST MOVE ON.

PARK REALIZED THE TIGERS ARE INTIMATELY LINKED TO THE PINES.

THIS IS MY FIRST EVIDENCE OF KOREAN PINE TREE FEEDING, LOOK AT THE SIZE OF THAT CONE!

SEE THAT, THIS IS WHERE THE NUTS SIT IN HERE.

THE PINE NUTS -- AND JUST ABOUT EVERYTHING IN THIS FOREST RELIES ON THESE.

HARD TO BELIEVE THAT THIS IS WHAT ALL THE FUSS IS ABOUT.

INNOCUOUS AS IT LOOKS, THIS TINY THING IS RESPONSIBLE FOR PROPPING UP THIS WHOLE ECOSYSTEM HERE AND EVERYTHING THAT THE TIGER DEPENDS UPON.

AS WE HIKE, I AM PUTTING OUT MORE CAMERA TRAPS, BUT I'M NOT JUST AFTER SHOTS OF ANIMALS.

I WANT TO SEE HOW THIS COMPLEX ECOSYSTEM WORKS.

ONLY BY DISCOVERING WHAT'S REALLY GOING ON CAN WE HOPE TO SAVE TIGERS AND BEARS.

PARK WAS DEVASTATED THAT THE NEW GENERATION OF TIGERS ON THE COAST FAILED TO SURVIVE.

HE HEADED INLAND IN SEARCH OF THE LAST REMAINING TIGER, THE FEMALE, SNOW WHITE.

HIS GROWING INSTINCT LED HIM TO A SPECIAL PLACE, A SHANGRI-LA, RICH IN KOREAN PINE -- AND THE TIGERS' PREY THAT DEPEND ON IT.

THIS IS GREAT!

IT'S SO NICE, BECAUSE I CAN PICTURE THE FILM IN MY MIND.

THIS IS IT.

THE GROUND WAS FROZEN SO SOLID, PARK COULDN'T DIG A HOLE.

INSTEAD HE HID 15 FEET UP A TREE, PERCHED ON A TINY PLATFORM.

OH, YES, YEAH, THE WEDGES.

CUT OUT OF THE SIDE OF THE TREE THERE.

MIND BLOWING.

MY RESPECT FOR YOU IS VERY HIGH.

[ LAUGHING ] PARK WAITED HERE FOR SO LONG WITHOUT SEEING ANY TIGERS, HE EVEN BEGAN TO FILM SNOWFALLS.

PARK HOPED THEIR MOTHER WAS HUNTING -- THEY WOULDN'T SURVIVE LONG WITHOUT HER.

[ WATER GURGLING ] HE CHOSE THIS SPOT BECAUSE OF A HOT SPRING...

CONFIDENT TIGERS WOULD DRINK AT A SMALL HOLE IN THE ICE, KEPT OPEN BY THE WARM WATER.

BROTHER AND SISTER, LOST IN FAIRYTALE WOODS, HANSEL AND GRETEL HAD THE PERFECT NAMES.

THE YOUNG MALE CAT IS CURIOUS.

HE INVESTIGATES THE CAMERAS.

HIS SISTER HANGS BACK NERVOUSLY.

IT TOOK PARK SUCH FAITH TO WAIT HERE -- THESE SCENES ARE HIS REWARD.

AMAZING, I WOULD FALL OFF.

I WOULD FALL OFF THE PLATFORM.

DID YOU, LIKE -- [ GASPS ] HE CAN STILL RECOGNIZE EACH TRUNK AND BRANCH.

PARK WAS HAPPY ENOUGH FILMING HANSEL AND GRETEL, BUT WHEN THEY RETURNED WITH THEIR MOTHER, HE KNEW HE HAD FOUND SNOW WHITE.

SHE HAD SURVIVED.

PARK HAD ANOTHER FAMILY TO WATCH AND FILM.

HE REMAINED UP HIS TREE, UNHARMED.

PERHAPS, AFTER ALL THIS TIME, SNOW WHITE TOLERATED HIS PRESENCE.

HE HADN'T JUST ENTERED THE TIGER'S WORLD, HE WAS NOW PART OF IT.

THESE SHOTS OF TIGERS WOULD BE HARD TO FILM ANYWHERE.

FOR WILD SIBERIAN TIGERS, THEY WERE MEANT TO BE IMPOSSIBLE.

OVER THE YEARS, WALKING HUNDREDS OF MILES, SLEEPING ALONE IN THE FOREST FOR MONTHS ON END, PARK HAD FOLLOWED THREE GENERATIONS OF HIS TIGER FAMILY.

WHEN YOU GO, WHEN YOU LEAVE, AND I TRY A TREE STAND OR A HIDE, WHAT'S THE BEST ADVICE?

DO YOU UNDERSTAND?

PARK ISN'T A RECLUSE -- HE DIDN'T LIKE BEING ALONE, AND HE MISSED HIS FAMILY.

HIS ENDURANCE IS WHAT MAKES HIM DIFFERENT TO MOST OF US.

AND THE PLACE ITSELF KEPT HIM GOING.

HE WAITED FOR TIGERS LIKE A FOREST WAITING FOR SPRING.

THANK YOU FOR LETTING ME INTO YOUR WORLD.

ALL RIGHT, MY FRIEND, BE SAFE.

TAKE CARE.

IT WILL BE A DIFFERENT PLACE IN THIS FOREST WITHOUT HIM, I THINK.

[ BIRDS CALLING ] PARK HAS LEFT, BUT I AM HEADING BACK IN TO TRY AND EXPERIENCE THE WILDERNESS AS HE DID.

6:00 A.M., I JUST WOKE UP, HAD A COUPLE OF HOURS' SLEEP AND THE COLD WOKE ME UP.

I HAD TO GET UP AND PUT SOME MORE CLOTHES ON AND A WARMER HAT.

[ RAPID THUMPING ] THERE'S A WOODPECKER.

THE FIRST INDICATION THAT THERE'S REALLY ANY OTHER ANIMAL AROUND IS THAT WOODPECKER.

[ WOODPECKER DRUMMING ON TREE ] HE'S QUITE CLOSE.

IT JUST GIVES ME A HUGE LEVEL OF RESPECT FOR WHAT PARK HAS ACCOMPLISHED.

THE SIT-AND-WAIT STRATEGY IS NOT FOR ME.

[ CHUCKLES ] A FRESH SNOWFALL, A NEW CHAPTER IN THE WHITE BOOK.

I MUST READ WITHOUT MY GUIDE.

CAT TRACKS -- SUDDENLY THE FOOTSTEPS ARE VERY MUCH CLOSER TOGETHER.

SMALL WILDCAT CROSSES THE ROAD RIGHT HERE AND JOINS THE MANCHURIAN HARE TRACKS.

DEER TRACKS...

IT'S A GREAT SPOT.

ON WHAT LOOKS LIKE WOULD BE A REALLY GOOD CHOICE FOR A TIGER SCENT-MARKING TREE.

[ SNIFFING ] OH, LOOK AT THAT.

AH!

AH!

I BELIEVE THAT IS A TIGER HAIR.

IT LOOKS LIKE SOMETHING HAS BRUSHED ITS FACE AGAINST IT RIGHT HERE.

THERE'S ANOTHER HAIR RIGHT THERE.

ANOTHER ONE HERE.

ALL UP AND DOWN THIS AREA.

YOU CAN IMAGINE THIS TIGER COMING UP TO THIS TREE, WALKING ALONG THIS ROAD HERE, THIS BEING A PERFECTLY ANGLED BIRCH TREE.

COMING UP TO IT, SMELLING WHO WAS HERE PREVIOUSLY.

GRABBING HIS PAWS AROUND IT, WHICH WOULD HAVE REACHED BEYOND MY REACH.

HIS FRONT PAWS UP THERE.

THEN HIS FACE... RUBBING IT LIKE THIS, AND THERE'S THE WHISKER MARKS.

PERFECT, JUST LIKE YOUR HOUSE CAT DOES ON THE EDGE OF THE COUCH.

THE FIRST SIGNS OF TIGER I FOUND ON MY OWN -- MY TEACHER WOULD BE PROUD.

I SPOTTED THE TREE BY THINKING LIKE A TIGER, BY THINKING LIKE PARK.

I AM GETTING CLOSER EACH DAY.

I'VE JUST FOUND THIS AND I AM VERY EXCITED, MY HEART IS POUNDING.

THIS IS A SCRAPE, THIS IS WHAT A TIGER WOULD DO -- THEY WOULD SCRAPE INTO THE GROUND LIKE THIS, AND PARK, JUST A COUPLE OF DAYS AGO, WAS TELLING ME THAT EACH TIGER HAS A DIFFERENT WAY OF DOING THIS.

SOME OF THEM CREATE A WIDE, SHALLOW SCRAPE, SOME OF THEM CREATE A REALLY DEEP, NARROW SCRAPE.

HE SAID KING BIG WOULD GO RIGHT DOWN UNTIL HE COULDN'T GO ANY FURTHER, REALLY DEEP, AND THEN THEY PEE OR DEFECATE RIGHT HERE.

IF IT WAS A BOAR IT WOULD BE MORE RANDOM, JUST PUSHING UP THE SNOW IN ANY DIRECTION.

BUT THIS, EVEN THE GRASS IS FACING THIS WAY.

LET ME LOOK AT OUR TRACKS FROM THIS MORNING A BIT MORE CAREFULLY.

THE THOUGHT THAT THERE WAS A TIGER RIGHT HERE AT ANY POINT IS GREAT, THOUGH.

I JUST WISH I COULD FIND SOME FRESH TRACKS TO HELP VERIFY THE SITUATION.

CAN'T YOU JUST IMAGINE HIM, AFTER WE PASS THROUGH HERE, YOU CAN JUST IMAGINE THAT TIGER CATCHING OUR SCENT, 'CAUSE WE STINK TO A TIGER, THAT'S FOR SURE.

AND HIM COMING TO EXPLORE ONCE WE'RE WELL UP THE TRAIL.

'CAUSE WE WENT AT LEAST TWO MILES BEYOND THIS.

SO, HE MIGHT HAVE BEEN CONFIDENT ENOUGH TO COME IN.

THE TIGERS ARE EVERYWHERE, BUT NOWHERE.

FOR MY LAST WEEK, I'M COLLECTING MY CAMERAS.

I HAVE PUT OUT TEN.

PARK USED MANY MORE, OVER A MUCH LONGER TIME.

I'D LOVE TO SEE ANY ANIMALS ON MY CAMERAS.

[ REVIEWING FOOTAGE ] NOT A THING... NOT A THING.

I'VE COPIED PARK AND USED A HOT SPRING AS BAIT.

I HAVE HIGH HOPES FOR THIS CAMERA.

YOU WOULDN'T BE BLAMED FOR THINKING THAT THERE'S ABSOLUTELY NO ANIMALS IN THIS FOREST, ACTUALLY.

OH!

OH, LEAVES!

[ LAUGHS ] I THOUGHT A BIRD JUST FLEW IN, BUT IT WAS LEAVES.

LISTEN TO THAT WIND.

FROM THE EIGHT CAMERAS SO FAR, ALL I HAVE IS TEN HOURS OF FALSE TRIGGERS, WIND AND LEAVES.

LOOKING ACROSS THE EMPTY FOREST, IT SEEMS HARDLY SURPRISING THAT I HAVE CAUGHT SO LITTLE ON CAMERA.

IN PARK'S FOOTAGE, THE FORESTS ARE TEEMING WITH LIFE.

I GUESS THAT'S PART OF ITS MAGIC.

PARK WAS ABLE TO FILM SNOW WHITE, HANSEL AND GRETEL THROUGHOUT THE FINAL WINTER, WATCHING THE CUBS LEARN AND GROW.

THE FAIRY-TALE ENDING TO HIS TIGER QUEST.

I'M STARTING TO GRASP WHAT KEPT HIM GOING.

THE HOPE THAT A TIGER WILL REVEAL ITSELF IS OVERWHELMING.

TODAY, HANSEL AND GRETEL WOULD BE SEVEN YEARS OLD -- TIGERS IN THEIR PRIME, IF THEY'VE AVOIDED THE POACHERS' TRAPS.

NOBODY IS LIKELY TO REPEAT PARK'S OBSESSION, OR HIS SUCCESS.

THESE FORESTS ARE DISAPPEARING RIGHT ACROSS THE RUSSIAN FAR EAST.

WHEN THEY ARE GONE, SCENES LIKE THIS WILL BE A THING OF THE PAST.

I'VE RETRACED MY STEPS TO WHERE MY JOURNEY WITH PARK BEGAN, TO COLLECT THE FIRST CAMERAS WE PUT OUT A FEW WEEKS AGO.

OKAY, THESE ARE THE LAST FOUR CAMERA TRAPS, SO MY LAST CHANCE TO CAPTURE SOMETHING ON FILM.

SIKA DEER -- NICE TIGER PREY.

NO, NOTHING ELSE.

HMM?

OKAY, MOST OF THESE ARE ME SETTING IT UP.

[ LAUGHS ] OH, WHAT IS THAT?

WOW!

A RACCOON DOG.

NICE!

I SAW RACCOON DOG SCAT ALL THE WAY UP TO THIS CAMERA.

SUCH A CRAZY LOOKING ANIMAL, AN ABSOLUTE CROSS BETWEEN A DOG AND A RACCOON.

OH!

WILD CAT!

THANK GOODNESS WE GOT SOMETHING.

[ GASPS ] [ SHUDDERS ] YOU'RE NOT GOING TO BELIEVE THIS... WE'VE GOT A TIGER!

WE'VE GOT A TIGER!

THERE IS A TIGER ON THIS CAMERA.

I CANNOT BELIEVE IT.

MY HEART IS POUNDING OUT OF MY CHEST.

I CANNOT BELIEVE IT!

OH!

AMAZING, I CAN EVEN HEAR THE ICE CRACKING AS SHE CAUTIOUSLY CROSSES THE FROZEN RIVER.

I CAN'T BELIEVE IT!

THAT'S OUR SECOND-TO-LAST CAMERA, ALL THIS WORK, ALL THESE MILES.

THERE ARE TIGERS HERE.

[ ICE CREAKING ] I WAS BEGINNING TO WONDER.

I DIDN'T THINK I WOULD BE CAPABLE OF ENDURING PARK'S ORDEAL.

BUT IF I FEEL LIKE THIS ON SEEING MY ONE TIGER, ON MY CAMERA, PERHAPS I AM.

I DIDN'T SEE IT WITH MY OWN EYES, AND I'M FINE WITH THAT -- STAYING AWAY FROM HUMANS IS THE BEST CHANCE THESE TIGERS HAVE.

AND WHEN PARK SAW HOW CAREFULLY MY TIGER CROSSES THE CREAKING ICE, HE INSTANTLY RECOGNIZED AN OLD FRIEND... GRETEL, THE FAIRYTALE TIGER HE FIRST FILMED ALL THOSE YEARS AGO.

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