Narrator: HIGH IN THE WILD COUNTRY OF YELLOWSTONE, THERE LIES THE PERFECT VALLEY.

[ HOWLING ] PERFECT, THAT IS, FOR WOLVES.

BUT THE VALLEY IS SO RICH EVERYONE WANTS TO STAKE A CLAIM.

[ GROWLING ] [ FIGHTING ] [ BEAR GROWLING ] ONE WOLF PACK, CALLED THE DRUIDS, HAS LONG RULED THIS PLACE.

BUT THEY ARE ABOUT TO FACE THEIR FIERCEST RIVALS AND THEIR GREATEST CHALLENGE.

WHEN THE WOLVES FINALLY MEET, THEY RISK THEIR FAMILIES, THEIR FUTURES, AND THEIR VERY LIVES TO CLAIM IT ALL...

IN THE VALLEY OF THE WOLVES.

Narrator: THIS IS A TALE OF QUEST AND CONQUEST, A STRUGGLE FOR LAND AND LEGACY.

ITS TWISTS AND TURNS TAKE THREE YEARS TO UNFOLD.

IT BEGINS IN WINTER, JUST BEFORE SUNRISE.

[ WOLVES HOWLING ] [ HOWLING INTENSIFIES ] [ HOWLING, BARKING ] FOR THE DRUID PEAK PACK, THE LAMAR VALLEY IN NORTHERN YELLOWSTONE HAS ALWAYS BEEN HOME.

THE DRUIDS HAVE RULED THIS VALLEY FOR EIGHT YEARS.

AT THEIR PEAK, THEY WERE A GREAT CLAN OF 37 WOLVES, ONE OF THE LARGEST WOLF PACKS EVER RECORDED.

BUT THAT WAS ALMOST TWO YEARS AGO, WHEN THEIR LEADER WAS IN HIS PRIME.

HE'S KNOWN BY THE RESEARCH COLLAR HE WEARS AS WOLF NUMBER 21.

COME APRIL, HE WILL TURN NINE YEARS OLD.

HAVING LIVED ALMOST TWICE AS LONG AS THE AVERAGE WOLF IN THE WILD, HE'S ONE OF THE OLDEST WOLVES IN THE NORTHERN RANGE.

YET ALONG WITH HIS MATE, ALPHA FEMALE 42, HE STILL KEEPS THE DRUIDS TOGETHER, HELPING TO FEED AND PROTECT THEM.

THE EARLY MORNING HOWL WAS NO CASUAL CONVERSATION.

IT WAS THE DRUID CALL TO ARMS.

WOLVES ARE BORN TO HUNT, AND LAMAR VALLEY IS THE FINEST HUNTING GROUND IN ALL OF YELLOWSTONE.

EACH WINTER, SOME 2,000 ELK FROM YELLOWSTONE'S NORTHERN HERD DESCEND INTO LAMAR.

THE VALLEY IS SURROUNDED BY MOUNTAINS AND SHELTERED FROM THE DEEPEST SNOW.

A MILE AND A HALF WIDE AND THIRTY MILES LONG, THIS IS THE BEST WINTER RANGE IN YELLOWSTONE.

BUT THOUGH THE VALLEY IS THE KEY TO THE ELK'S SURVIVAL, HERE THEY MUST FACE THE WOLVES.

[ WOLVES CALLING ] THE YOUNG DRUIDS LEAP FORWARD, FULL OF SPEED AND STAMINA.

THEY CHASE AND TEST THE ELK.

CHASE AND TEST... UNTIL THEY FIND A WEAKNESS.

OLD 21 GAMELY PLAYS HIS PART.

THE YOUNGSTERS DO MOST OF THE LEGWORK, BUT WHEN IT'S OVER, ALL THE DRUIDS SHARE THE REWARD.

A PACK THIS SIZE MUST KILL EVERY TWO OR THREE DAYS, AND THIS SUPPORTS MANY OTHER RESIDENTS OF THE VALLEY.

RAVENS AND MAGPIES ARE SO QUICK ON THE SCENE, THEY OFTEN BEAT THE REST OF THE CLAN TO THE KILL.

AND IT'S NOT JUST FOOD THEY'RE AFTER.

A PAIR OF RAVENS MAKES OFF WITH A BIT OF FUR, PERFECT FOR RENOVATING THEIR NEST THIS TIME OF YEAR.

BUT SCAVENGERS NEED TO BE CAUTIOUS.

IT'S ALWAYS WISE TO GIVE WOLVES A WIDE BERTH.

THE LITTLE RED FOX HAS SECOND THOUGHTS.

HE WON'T RETURN UNTIL THE DRUIDS ARE LONG GONE.

BUT THIS PAIR OF COYOTES CAN BE TOO BOLD FOR THEIR OWN GOOD.

WHILE THE WOLVES ARE STILL AT THE CARCASS, THE SMART MOVE IS TO HANG BACK.

SOMETIMES WOLVES ARE WILLING TO SHARE, BUT MORE OFTEN, THEY GET TOUCHY ABOUT THEIR HARD-EARNED PROPERTY.

BUT THE DRUIDS ARE TOO FULL TO MOVE.

IF THEY HAVEN'T EATEN IN SEVERAL DAYS, THEY WILL GORGE AND CONSUME 20 POUNDS IN A SINGLE MEAL.

ABOUT ALL THEY CAN MANAGE NOW IS A NAP.

STILL, THE COYOTES APPROACH WITH CAUTION.

THEY CAN NEVER BE SURE WHEN WOLVES WILL TURN.

AND THERE'S JUST SOMETHING ABOUT COYOTES THAT SETS THEM OFF.

THE DRUIDS ARE NOT OUT FOR BLOOD THIS TIME, BUT THE COYOTE COUPLE HAS HAD A SCARE.

THEY'LL GET NO SHARE OF THE WOLVES' KILL NOW, AND MUST CATCH A MEAL ON THEIR OWN.

RUSTLING AROUND IN THE FROZEN GRASS, A VOLE GETS CARELESS.

THIS IS THE COYOTE'S USUAL PREY.

AT LEAST THIS MUCH OF THE VALLEY IS HIS.

THE COYOTE COUPLE SETTLES DOWN FOR THE NIGHT.

AS MATES, THEY SHARE A TERRITORY IN THE VALLEY AND A BOND THAT WILL LAST FOR LIFE.

A HARDY FLOCK OF WAXWINGS HAS BEEN FEEDING ON JUNIPER BERRIES ALL WINTER, AND IN YELLOWSTONE, THAT'S SIX MONTHS LONG.

YET WITH TWO MONTHS OF WINTER STILL TO GO, A HINT OF SPRING IS IN THE AIR.

A LONE BLACK WOLF IS COMING TO CALL ON THE DRUIDS.

HE'S NOT JUST ANY WOLF, HE IS 302 -- THE MOST NOTORIOUS FLIRT IN YELLOWSTONE.

HE COMES FROM A CLAN ALMOST 20 MILES AWAY, BUT ALL THE DRUIDS KNOW HIM WELL.

THIS IS THE SECOND YEAR HE HAS APPROACHED THE PACK.

[ HOWLING ] 21 AND HIS MATE ARE NOT EXACTLY PLEASED TO SEE HIM.

THEIR DAUGHTER, HOWEVER, CAN HARDLY CONTAIN HERSELF.

[ GRUNTING ] [ YELPS ] [ GROWLS ] 302 KEEPS ONE EYE ON THE DAUGHTER, AND ONE ON THE OLD MAN.

[ WHINING, GRUNTING ] FINALLY, 21 HAS HAD ENOUGH.

302 BEATS A HASTY RETREAT.

HE'S MORE OF A CASANOVA -- A LOVER NOT A FIGHTER.

HE WANTS NO PART OF CHALLENGING THE OLD CHIEF.

THE DAUGHTER SLINKS HOME TO HER MOTHER.

BUT THIS IS A BATTLE PARENTS NEVER WIN.

THEIR DAUGHTER'S LONGING IS BEYOND THEIR CONTROL.

THIS IS THE MATING SEASON, AND NOT JUST FOR WOLVES.

THE MATING SEASON IS SOMETHING COYOTES AND WOLVES HAVE IN COMMON, AND THE LITTLE COYOTE COUPLE HEADS OFF FOR A MOMENT TO THEMSELVES.

[ FEMALE COYOTE SNARLING ] IN TWO MONTHS, BOTH COYOTES AND WOLVES WILL GIVE BIRTH, AND THE VALLEY WILL BECOME THE PLAYGROUND OF A NEW GENERATION OF PUPS.

[ YIPPING ] THE NEXT DAY, THE CASANOVA IS BACK FOR MORE.

HE COURTS THE FEMALES, BUT WHAT HE REALLY WANTS IS TO JOIN THE CLAN -- AN IDEA THAT SEEMS TO AGREE WITH ALL THE DRUID DAUGHTERS.

[ WHINING ] THOUGH THIS IS THE USUAL WAY A WOLF CHANGES CLANS, THE ALPHA PAIR WILL NOT ALLOW IT.

TOGETHER, THEY SEND THE CASANOVA PACKING.

THE OLD COUPLE STILL MAKES A FORMIDABLE TEAM.

THEY RESTORE ORDER TO THEIR VALLEY, BUT IT WON'T LAST FOR LONG.

THEY ARE AT THE END OF THEIR REIGN.

WITHIN A WEEK, THE ALPHA FEMALE WILL BE DEAD, KILLED BY ANOTHER PACK.

IN A FEW SHORT MONTHS, 21 WILL FOLLOW HER.

HIS BONES WILL BE FOUND LYING ON A RIDGE ABOVE THE VALLEY.

IT'S THE END OF AN ERA.

THE TALE IS ABOUT TO TURN FOR THE DRUIDS OF LAMAR.

TROUBLE COMES FIRST FROM THEIR WESTERN FRONTIER AS A RIVAL PACK CHALLENGES THEIR BORDER.

[ BARKING, BAYING ] THE INVADERS SENSE THAT, WITHOUT THEIR OLD LEADERS, THE DRUIDS ARE NOT THE CLAN THEY USED TO BE.

[ BARKING, HOWLING ] BUT THE DRUIDS RALLY, AND WITH A QUICK COUNCIL, SWING INTO ACTION.

EVENLY MATCHED, NEITHER CLAN WILL CROSS THE BORDER.

AND FOR NOW THE DRUIDS HOLD THE LINE.

THE DRUIDS HAVE MADE A KILL, AND THIS TIME LEAVE PLENTY FOR THE COYOTE COUPLE.

BUT THERE'S NEVER ENOUGH FOR EVERYONE.

THE MALE COYOTE TAKES HIS TO GO.

NOW THE EAGLE CAN MOVE IN, BUT EVEN HE CAN'T EAT IN PEACE.

THE FEMALE COYOTE TAKES A MODEST SHARE, BUT KEEPS AN EYE OUT FOR TROUBLE.

WHEN IT STRIKES, SHE CAN'T SEE IT COMING.

THE MALE HANGS ON TIGHT TO HIS PRIZE, WHILE THE FEMALE WASHES AWAY ALL THAT'S LEFT OF HERS.

[ CROWING ] AS WINTER RETREATS FROM LAMAR, A NEW THREAT TO THE DRUIDS INVADES THE VALLEY -- A STRONG PACK OF 15 FROM SLOUGH CREEK TO THE NORTH.

THEY'RE ALREADY DEEP INTO DRUID TERRITORY, INTENT ON CONQUEST.

THE DRUIDS RESPOND, BUT THEIR STRENGTH HAS DIMINISHED.

NOW, THEY ARE ONLY NINE.

THE SLOUGHS CAN HEAR THE DRUID'S WEAKNESS, AND ATTACK.

THOUGH OUTNUMBERED, THE DRUIDS SET OUT TO MEET THEM.

TAILS WAVING HIGH WITH CONFIDENCE, THE SLOUGHS SMELL VICTORY.

BUT THE DRUIDS ARE FIGHTING FOR EVERYTHING THEY OWN.

THE BATTLE BEGINS IN CONFUSION.

THE YOUNG DRUIDS DON'T KNOW WHAT TO DO.

THEN THE CHIEF OF THE SLOUGHS TAKES CHARGE, ATTACKING THE DRUID'S NEW LEADER.

[ BARKING, YELPING, GROWLING ] THE DRUIDS ARE ON THE RUN.

THE BEST THEY CAN DO IS ESCAPE WITH THEIR LIVES.

THE ONCE-MIGHTY DRUID CLAN SCATTERS.

BOUND FOR HARD TIMES, THEY HEAD INTO EXILE.

THE SLOUGHS BEGIN TO GATHER.

THEY'VE DONE WHAT NO OTHER PACK HAS BEEN ABLE TO DO IN ALMOST 10 YEARS.

THEY'VE BROKEN THE DRUIDS AND TAKEN LAMAR, THE GREATEST PRIZE IN YELLOWSTONE, AND THEY KNOW IT.

THEIR VICTORY CELEBRATION IS LOUD AND LONG.

[ CLAN HOWLING ] [ HOWLING CONTINUES ] FOR THE COYOTES, IT'S A SEISMIC CHANGE.

THE DRUIDS WERE THE DEVIL THEY KNEW.

WHAT KIND OF OVERLORDS WILL THE SLOUGH CREEK WOLVES BE?

THEY'VE ALREADY MADE A KILL... AND THE MALE COYOTE MOVES IN AS USUAL.

THIS TIME, IT'S A TERRIBLE MISTAKE.

FLUSH WITH THEIR NEW POWER, THE SLOUGHS SET OUT TO DELIVER A MESSAGE.

THEY SHOW NO MERCY.

THE FEMALE COYOTE HAS NO CHOICE BUT TO FLEE.

SHE LOOKS FOR HER MATE, BUT HE WON'T BE COMING.

[ CALLING ] THE FEMALE MUST CARRY ON ALONE.

SOON, SHE WILL HAVE PUPS TO CARE FOR -- BUT SHE WON'T HAVE THEM HERE WITH THE SLOUGHS IN CHARGE.

[ HOWLING ] TURNING SOUTH, SHE HEADS INTO UNFAMILIAR COUNTRY, INTO THE INTERIOR OF YELLOWSTONE.

WATER BECOMES WINTER'S FROZEN HIGHWAYS, AND SHE TRACKS ALONG THE YELLOWSTONE RIVER FOR ALMOST 20 MILES.

THIS ICY ROAD LEADS HER DIRECTLY TO THE BASE OF THE UPPER FALLS.

IT'S A RUGGED CLIMB, BUT IN THESE DARK, QUIET WOODS, SHE IS NOT THE ONLY TRAVELER.

A RED FOX HAS FOUND A CARCASS AND IS SCAVENGING A MEAL.

FOR THE FOX, THE COYOTE IS NOT A WELCOME SIGHT.

SHE'S AS INTIMIDATING TO HIM AS A WOLF IS TO THE COYOTE.

BUT THE FOX KNOWS HOW TO MAKE IT HERE, IN THE DEAD OF WINTER, ON HIS OWN.

HE VENTURES OUT INTO THE BRIGHT EXPANSE OF HAYDEN VALLEY.

THIS IS YELLOWSTONE'S HIGH PLATEAU, ALMOST 8,000 FEET IN ELEVATION.

WHILE WINTER IS RETREATING DOWN IN LAMAR, IT HANGS ON HERE WITH A VENGEANCE.

WEIGHING A MERE 10 POUNDS OR SO, THE FOX STEPS LIGHTLY ON THE FROZEN CRUST.

HIS PREY IS PROTECTED BY A GOOD THREE FEET OF SNOW.

YET WITH ONLY SENSITIVE EARS AND A POINTY NOSE, THE FOX IS WELL PREPARED.

AT 30 POUNDS, THE COYOTE KEEPS BREAKING THROUGH THE CRUSTY SNOW.

HER STRATEGY IS TO DIG.

AND DIG.

AND DIG.

BUT IN THE END IT'S WORTH IT.

BISON SPEND THE WINTER HERE BREAKING TRAIL AND PUSHING SNOW.

IT TAKES ALL THEIR MASSIVE STRENGTH TO REACH THE MEAGER GRASS BELOW.

THE ELK LEFT HAYDEN MONTHS AGO.

ONLY ONE OTHER CREATURE CAN MATCH THE BISON'S ABILITY TO ENDURE...

THE WINTER WOLVES OF HAYDEN.

THIS SMALL BUT REMARKABLE BAND HAS MADE AN EXTRAORDINARY CHOICE.

INSTEAD OF TAKING ON OTHER WOLVES FOR THE RICHES OF LAMAR, THEY STAY HERE AND TAKE ON THE FIERCEST PREY.

THESE WOLVES SURVIVE ON BISON.

THERE IS LITTLE FOR THE COYOTE HERE.

IT'S HARD ENOUGH FOR THE WOLVES.

THIS TOUGH LITTLE BAND HASN'T HAD MANY PUPS, AND HASN'T GROWN ANY LARGER.

HAYDEN VALLEY MAY NOT PROVIDE ENOUGH NUTRITION FOR THEM AT THE RIGHT TIME OF YEAR.

STILL, THEY'VE MANAGED TO BRING DOWN A BISON.

[ BAYING ] BUT THE COYOTE'S HAD ENOUGH OF WOLVES.

SHE NEEDS TO FIND A DEN SITE, SOME SAFE PLACE TO HAVE HER PUPS.

SHE CONTINUES ON HER SOLITARY WAY, LEAVING HAYDEN AND ITS WOLVES BEHIND.

AT LONG LAST, THE ICE BEGINS TO LET GO.

TRAFFIC PICKS UP ALL ALONG THE YELLOWSTONE RIVER.

JUST ALONG THE RIVERBANK, MOUNTAIN BLUEBIRDS ARE FLOCKING TO THE FIRST FEAST OF SPRING.

CADDIS FLIES ARE HATCHING.

THEY'VE SPENT THE WINTER IN LARVAL CASES IN THE RIVERBED AND NOW SPILL OUT FROM THE WATER AND MELTING ICE, BRINGING THE BIRDS BACK TO THE HIGH COUNTRY.

A GRIZZLY, JUST OUT OF HIS DEN, HEADS DOWN TO LAMAR FOR SOMETHING TO EAT.

BUT AFTER FASTING ALL WINTER, IT TAKES A FEW DAYS FOR HIS APPETITE TO GET BACK TO BEAR-SIZE.

HE JUST STARTS OUT WITH A SNACK.

MEANWHILE, THE SLOUGHS ARE WORKING HARD.

FOR MONTHS, THEY'VE BEEN PATROLLING TWO TERRITORIES -- THEIR HOME RANGE ALONG SLOUGH CREEK, PLUS LAMAR.

EACH CHASE IS AN ENDURANCE TEST -- FOR BOTH THE ELK AND THE WOLVES.

AFTER RUNNING FLAT OUT FOR ALMOST AN HOUR, THE WOLVES FINALLY SUCCEED.

[ BIRDS CALLING ] WITH WINTER OVER, THE SLOUGHS FACE A NEW CHALLENGER FOR TOP DOG OF THE VALLEY.

A GRIZZLY IS MORE THAN A MATCH FOR A WOLF OR TWO, AND WHEN ONE GETS WIND OF A KILL, THE WOLVES MUST STEP ASIDE.

[ GRIZZLY GROWLING ] AS LONG AS THE BEAR IS BIG ENOUGH, HE TAKES CONTROL OF THE CARCASS.

ALL THE GRIZZLY NEEDS TO WORRY ABOUT... IS ANOTHER GRIZZLY.

BUT A MOTHER AND HER CUBS ARE A VULNERABLE COMBINATION.

EVEN THE WOLF TRIES TO GIVE THEM A HARD TIME.

SHE'S SO MUCH SMALLER THAN THE BIG MALE ON THE CARCASS, SHE'S GOT A LOT OF NERVE APPROACHING HIM AT ALL.

[ BEARS GROWLING ] ONE QUICK CONFRONTATION IS ALL IT TAKES TO SETTLE THE ENTIRE SITUATION.

FAR ACROSS LAMAR, ALONG THE EASTERN SLOPES OF THE VALLEY, FOUR WOLVES SLIP THROUGH THE TREES.

THE TWO FEMALES ARE ALL THAT'S LEFT OF THE MIGHTY DRUID CLAN.

BUT WITH THEM IS 302, THE CASANOVA.

THOUGH IN EXILE AND FAR FROM POWER, THE CASANOVA HAS BECOME A DRUID AT LAST.

THE FOURTH WOLF IS HIS BROTHER.

PERHAPS TOGETHER THEY CAN REBUILD THE CLAN.

THE ONCE SOLITARY FOX IS NOW BUSY RAISING A FAMILY.

GONE IS HER THICK WINTER COAT.

[ YIPPING, GROWLING ] THE FOX KITS ARE ALL ENERGY AND HIGH SPIRITS, PLAYFUL LITTLE HUNTERS-TO-BE.

BUT THE WOLVES HAVE NOT BEEN SO LUCKY.

IT'S THE FIRST PUPPING SEASON IN LAMAR FOR THE SLOUGHS, AND THEY HAVE PRODUCED FOUR LITTERS.

BUT THE PUPS ARE DYING, ONE BY ONE.

THE KILLER IS AN UNIDENTIFIED VIRUS SWEEPING ACROSS THE NORTHERN RANGE.

IT COULD BE PARVO OR CANINE DISTEMPER BUT IT'S DEVASTATING TO WOLF PUPS.

THE SLOUGHS ARE HIT HARD.

OUT OF FIFTEEN PUPS, ONLY THREE SURVIVE.

[ HOWLS ] SUMMER FINALLY REACHES INTO THE DEEP INTERIOR OF YELLOWSTONE.

IT RELEASES THE FULL FORCE OF THE FALLS...

IT GREENS UP THE HIGH HAYDEN VALLEY... AND WARMS THE SHORES OF YELLOWSTONE LAKE.

THIS IS WHERE THE COYOTE FOUND HER SAFE HAVEN.

NOW SHE'S REARING THREE PUPS BY HERSELF.

THE PUPS ARE ALREADY EIGHT WEEKS OLD, AND ALMOST READY TO BE WEANED...

BUT NOT QUITE.

THEIR DEN SITE, FAR FROM LAMAR, HAS TURNED INTO A STROKE OF GOOD FORTUNE.

THE PUPS WON'T BE EXPOSED TO THE VIRUS THAT'S GRIPPING THE VALLEY.

THEIR MOTHER WORKS HARD KEEPING EVERYONE FED.

SHE'S DISCOVERED THE NEST OF A HAPLESS MERGANSER, AND STEALS THE EGGS TO GIVE TO THE PUPS.

[ PUP GROWLING ] FOR THE PUPS, THE LAKE IS A DAUNTING BUT IRRESISTIBLE PLAYMATE.

THEIR MOTHER HAS DONE HER BEST.

AND AS SUMMER UNFOLDS, MOTHERS ALL ACROSS YELLOWSTONE ARE DOING THE SAME.

[ BEAR AND CUBS GROWL ] LAMAR IS LUSH AND GREEN, BUT ALMOST EMPTY.

THE ELK HAVE DISPERSED INTO THE HIGH COUNTRY, AND WITH THEM WENT THE WOLVES.

THE VALLEY RECOVERS FROM WINTER'S WEAR AND TEAR.

THE GRASS HAS A CHANCE TO GROW.

FOR A FLEETING MONTH OR TWO, LAMAR BELONGS TO THE SMALLER HUNTERS THAT STAY BEHIND.

[ FROGS CROAKING ] ALL TOO SOON, THE LONG DAYS ARE OVER.

THE VALLEY TURNS FROM GREEN TO GOLD, GEARING UP FOR CHANGE.

IT'S TIME TO PUT ON A WARMER COAT... TO WORK THE LAST OF THE TALL GRASS.

WINTER DESCENDS AGAIN INTO LAMAR, THE VALLEY OF THE WOLVES.

BUT, STRANGELY, THE WOLVES SEEM TO BE MISSING.

[ YIPPING ] INSTEAD, COYOTES ARE GATHERING INTO WOLF-LIKE PACKS.

ALL ACROSS THE NORTHERN RANGE WOLVES HAVE SUFFERED A SETBACK.

THE LETHAL VIRUS HAS TAKEN A TERRIBLE TOLL.

FOR THE MOMENT, THE SLOUGHS HAVE RETREATED TO THEIR OLD HOME RANGE, GIVING THE COYOTES THE RUN OF THE VALLEY.

BUT IT'S NOT QUITE THAT SIMPLE FOR THE COYOTES.

THE FEWER THE WOLF KILLS, THE GREATER THE CONFLICT -- AT EVERY CARCASS.

[ GROWLING ] AND NOW THE COYOTES MUST POLICE EACH PRECIOUS KILL.

AFTER A STRANGE WINTER COMES AN EVEN STRANGER SPRING.

[ THUNDER ] A CURSE SEEMS TO HANG OVER LAMAR, DOGGING THE FOOTSTEPS OF THE SLOUGH CREEK PACK.

IT'S APRIL, THEIR SECOND PUPPING SEASON IN THE VALLEY, AND THEIR TROUBLES GO FROM BAD TO WORSE.

A MYSTERIOUS GANG OF TWELVE WOLVES FROM OUTSIDE YELLOWSTONE STEALS INTO LAMAR.

WITHIN DAYS, THEY KILL ONE OF THE SLOUGH MALES, AND A SECOND MALE GOES MISSING.

THEN SLOWLY, DELIBERATELY, THE UNKNOWN PACK CLIMBS THE WESTERN RIDGE, UP TO THE STEEP SITE OF THE SLOUGH'S DEN.

ON A CLIFF TO THE WEST THE SLOUGHS KEEP WATCH, BUT STRANGEST OF ALL MAKE NO ATTEMPT TO RETAKE THE DEN.

FOR 12 DAYS, THE UNKNOWN WOLVES CAMP OUT AT THE SITE.

THE SLOUGHS FAIL TO BREAK THEIR SIEGE.

THEY'RE UNABLE TO REACH THEIR PUPS WITH FOOD, AND THE PUPS ALL DIE IN THE DEN.

THE UNKNOWN WOLVES THEN WITHDRAW FROM THE VALLEY, EVEN MORE OF A MYSTERY THAN WHEN THEY CAME.

BUT AT THE FAR EASTERN EDGE OF LAMAR, FORTUNES ARE TURNING.

DOWN IN THE DRAW ALONG SODA BUTTE CREEK, 302 AND THE SMALL BAND OF DRUIDS ARE THRIVING.

THEY HUNT WITH A GRAND PURPOSE.

THEY HAVE PUPS TO FEED, DRUID PUPS, GROWING FAST.

FROM JUST TWO FEMALES HAVE COME ELEVEN NEW RECRUITS.

HERE IN EXILE, THE DRUIDS HAVE BEEN REBORN.

THE PUPS ARE THE STRENGTH, THE FUTURE OF THE CLAN.

WHEN THE PUPS ARE GROWN, MAYBE THE DRUIDS CAN RETURN TO THE VALLEY.

[ SNORTING, CALLING ] ONCE AGAIN, LAMAR RINGS WITH THE RITUALS OF AUTUMN.

[ ANTLERS CLASHING ] WITH NO PUPS TO ANCHOR THE PACK, THE SLOUGHS START TO SCATTER.

SOME HAVE BEEN KILLED OR DIED ON THEIR OWN.

SOME HAVE JUST DRIFTED AWAY.

THE HERDS START DOWN FROM THE HIGH COUNTRY, HEADING FOR WINTERING GROUNDS.

AND THE RUT OF BISON BULLS SHAKES THE VALLEY FLOOR.

IT'S NOT YET THE END OF SEPTEMBER, BUT ON THE SLOPES ABOVE LAMAR IT BEGINS TO SNOW.

STOCKING UP ON CALORIES FOR THE FASTING MONTHS TO COME, A GRIZZLY SEEKS ONE LAST HARVEST -- THE SEEDS OF THE WHITE BARK PINE.

A GOOD CROP WILL SEE HIM SAFELY THROUGH HIBERNATION.

IN A WEEK OR TWO, HE'LL BE TUCKED AWAY IN HIS DEN, LEAVING YELLOWSTONE TO WINTER... [ WOLVES HOWLING ] AND THE WOLVES.

FROM ALL ACROSS THE NORTHERN RANGE, THOUSANDS OF ELK ROLL INTO LAMAR LIKE A TIDE.

AND ON THEIR HEELS, FROM THE EASTERN REACHES OF THE VALLEY, COME THE DRUIDS.

OUT IN FRONT IS 302, THE CASANOVA.

HIS QUEST IS COMPLETE.

HE'S BRINGING HIS FAMILY AND HIS CLAN BACK TO THEIR LAND.

THESE ARE HIS PUPS, ALMOST FULL GROWN.

WRESTLING WITH AN OLD BISON SKIN, THE PUPS ARE BRIMMING WITH CONFIDENCE.

REACHING THE HEART OF THE VALLEY, THEY WAIT FOR A CHALLENGE...

BUT ALL IS QUIET.

THE SLOUGHS HAVE NO FIGHT LEFT IN THEM, AND SLIP AWAY UP THE RIDGE IN SILENCE.

THEY HAD TAKEN THIS PERFECT VALLEY, AND JUST COULDN'T KEEP IT.

BUT THEN, NOTHING WORTH HAVING IS EASY TO HOLD.

[ HOWLING ] THE DRUIDS WILL SURELY BE TESTED IN THE SEASONS TO COME, BUT TODAY, THE VALLEY IS THEIRS.

THE DRUIDS HAVE COME HOME.

[ HOWLING ]