Alaskans prepare for the winter months; Andy hunts moose; Sue heads to Fairbanks for a foot procedure; the hailstones teach their daughters to ice fish; Glenn repairs his cabin.

With over six billion of them across the planet, smartphones have changed the modern world; with rare access to electronics giant Samsung, Hannah uncovers the technological game changers that have made the smartphone a reality.

The dry season is now upon the animals of the Serengeti, turning the waterhole into a death trap for the herds, but for some this season is a gift.

Alaskans prepare for the winter months; Andy hunts moose; Sue heads to Fairbanks for a foot procedure; the hailstones teach their daughters to ice fish; Glenn repairs his cabin.

Hope and Allison look to gain more experience with pelicans by heading to southern California.

Exploring some of the most cavernous places on the planet, including an expansive Siberian crater with no explainable origin, Greenland's bizarre black holes, an ancient forbidden well in the Yemeni desert, and a voluminous void in Antarctica.

Rumoured to be the cleanest river in Europe, few dispute it's the coldest; cascading down from the Dinaric Alps in Serbia, it soon crosses the border into Bosnia Herzegovina, where marine biologist and fisherman Sanel Riđanović casts for salmon.

Hope and Allison look to gain more experience with pelicans by heading to southern California.

Exploring some of the most cavernous places on the planet, including an expansive Siberian crater with no explainable origin, Greenland's bizarre black holes, an ancient forbidden well in the Yemeni desert, and a voluminous void in Antarctica.

Rumoured to be the cleanest river in Europe, few dispute it's the coldest; cascading down from the Dinaric Alps in Serbia, it soon crosses the border into Bosnia Herzegovina, where marine biologist and fisherman Sanel Riđanović casts for salmon.

Hope and Allison look to gain more experience with pelicans by heading to southern California.

Sue travels 150 miles to investigate squatters on her property; Andy's sled begins to fall apart while he's collecting firewood; Chip and Agnes brave thin ice to harvest whitefish.

Hannah Fry discovers the hidden WWII radar technology that heats up baked beans; she learns the legend of the melted candy bar in an engineer's pocket that kick-started a kitchen revolution; she demonstrates why microwaves zap food but not people.

The four categories of cute in the animal kingdom and the scientific stories behind why animals are cute.

Without volcanoes, life on Earth would never have begun; they are responsible for both the planet's breathable atmosphere and the oceans; mineral-rich ash from regular eruptions fertilize the land.

Wonders created by the power of water include Victoria Falls, where men take risks to reach fishing pools; the Camargue, where a man duels with a bull; ocean reefs.

Sue travels 150 miles to investigate squatters on her property; Andy's sled begins to fall apart while he's collecting firewood; Chip and Agnes brave thin ice to harvest whitefish.

A Spinosaurus, the world's largest ever predatory dinosaur, struggles to bring up his babies and lead his young family across one of the deadliest environments on Earth.

In summer's home stretch, family ties run deep; Cole hunts for protein in the rain; Jessie gathers the last of the warm weather bounty; the Hailstones track shy prey; Ricko's legacy project.

Chris starts his season with a massive catch of Tullibee, only to see his happiness cut short; Justin and Mike start in Hecla and hit the motherlode; a critical fish market closes; Richard's close call on the ice.

Levison and Alberto travel through Guatemala, Honduras and Nicaragua.

In summer's home stretch, family ties run deep; Cole hunts for protein in the rain; Jessie gathers the last of the warm weather bounty; the Hailstones track shy prey; Ricko's legacy project.

Chris starts his season with a massive catch of Tullibee, only to see his happiness cut short; Justin and Mike start in Hecla and hit the motherlode; a critical fish market closes; Richard's close call on the ice.

Levison and Alberto travel through Guatemala, Honduras and Nicaragua.

Sue travels 150 miles to investigate squatters on her property; Andy's sled begins to fall apart while he's collecting firewood; Chip and Agnes brave thin ice to harvest whitefish.

Hannah Fry discovers the hidden WWII radar technology that heats up baked beans; she learns the legend of the melted candy bar in an engineer's pocket that kick-started a kitchen revolution; she demonstrates why microwaves zap food but not people.

Chris starts his season with a massive catch of Tullibee, only to see his happiness cut short; Justin and Mike start in Hecla and hit the motherlode; a critical fish market closes; Richard's close call on the ice.

Sue travels 150 miles to investigate squatters on her property; Andy's sled begins to fall apart while he's collecting firewood; Chip and Agnes brave thin ice to harvest whitefish.

Hope learns all she can from a birds of prey rehab.

A perfect circle carved around an ancient peak; a scary phenomenon in the Pacific; strange shapes in a Middle Eastern desert; a formation below the ocean's surface.

Tackling the grade 6 rapids and untamed waters of the Buller River on the west coast of New Zealand's South Island, blessed by a Māori elder of the Ngāti Apa ki te Rā Tō.

Hope learns all she can from a birds of prey rehab.

A perfect circle carved around an ancient peak; a scary phenomenon in the Pacific; strange shapes in a Middle Eastern desert; a formation below the ocean's surface.

Tackling the grade 6 rapids and untamed waters of the Buller River on the west coast of New Zealand's South Island, blessed by a Māori elder of the Ngāti Apa ki te Rā Tō.

Hope learns all she can from a birds of prey rehab.

Chip builds a freight sled for winter travel; Sue is forced to brave a dangerous road to get home after a blizzard strands her in Fairbanks; Andy and Kate get their sled dogs ready for winter; Glenn tries to harvest meat for the winter.

Hannah Fry visits headphone honchos Bose to find out how the teeny earbud tech works and meets the human testers with "golden ears.".

In summer's home stretch, family ties run deep; Cole hunts for protein in the rain; Jessie gathers the last of the warm weather bounty; the Hailstones track shy prey; Ricko's legacy project.

Chris starts his season with a massive catch of Tullibee, only to see his happiness cut short; Justin and Mike start in Hecla and hit the motherlode; a critical fish market closes; Richard's close call on the ice.

Levison and Alberto travel through Guatemala, Honduras and Nicaragua.

Chip builds a freight sled for winter travel; Sue is forced to brave a dangerous road to get home after a blizzard strands her in Fairbanks; Andy and Kate get their sled dogs ready for winter; Glenn tries to harvest meat for the winter.

It's time to close another chapter in the lives of the animals of the Serengeti; first, all around is a blackened wasteland, the aftermath of the huge fire.

The Trappist-1 stellar system is home to seven Earth-like planets, and one of them could harbor life; rival teams of visionary pioneers use data to extrapolate entire worlds, leading the search for life on other planets throughout the universe.

Challenging the concept of reality with new data from a supermassive black hole.

Dr. Helen Czerski reveals how the harnessing of heat's power to transform matter has led to some of humanity's greatest achievements, from molten metal that enabled us to make tools to the searing heat of plasmas that offer near unlimited power.

The Trappist-1 stellar system is home to seven Earth-like planets, and one of them could harbor life; rival teams of visionary pioneers use data to extrapolate entire worlds, leading the search for life on other planets throughout the universe.

Challenging the concept of reality with new data from a supermassive black hole.

Dr. Helen Czerski reveals how the harnessing of heat's power to transform matter has led to some of humanity's greatest achievements, from molten metal that enabled us to make tools to the searing heat of plasmas that offer near unlimited power.

Chip builds a freight sled for winter travel; Sue is forced to brave a dangerous road to get home after a blizzard strands her in Fairbanks; Andy and Kate get their sled dogs ready for winter; Glenn tries to harvest meat for the winter.

Hannah Fry visits headphone honchos Bose to find out how the teeny earbud tech works and meets the human testers with "golden ears.".

It's time to close another chapter in the lives of the animals of the Serengeti; first, all around is a blackened wasteland, the aftermath of the huge fire.

Chip builds a freight sled for winter travel; Sue is forced to brave a dangerous road to get home after a blizzard strands her in Fairbanks; Andy and Kate get their sled dogs ready for winter; Glenn tries to harvest meat for the winter.

It's officially the third-highest snowfall in Manitoba in the last century; commercial fishers are plagued by deep drifts and hidden pockets of slush that can stop them in their tracks; Chris finds out the hard way that traveling alone is a bad idea.

Tempers flare as hunger, exhaustion, and no reprieve from one another pushes someone past the point of no return.

Michela, Brendan and Caleb struggle on the water as they make way to a new camp; a medicine woman brings the group knowledge and insights.

Griff uncovers what makes Newfoundland and Labrador unique, from tiny islands, sea shanties and cods tongues to jellybean houses and noonday canons, while discovering its bigness in land, dogs and the hospitality of its people.

It's officially the third-highest snowfall in Manitoba in the last century; commercial fishers are plagued by deep drifts and hidden pockets of slush that can stop them in their tracks; Chris finds out the hard way that traveling alone is a bad idea.

Tempers flare as hunger, exhaustion, and no reprieve from one another pushes someone past the point of no return.

Michela, Brendan and Caleb struggle on the water as they make way to a new camp; a medicine woman brings the group knowledge and insights.

Griff uncovers what makes Newfoundland and Labrador unique, from tiny islands, sea shanties and cods tongues to jellybean houses and noonday canons, while discovering its bigness in land, dogs and the hospitality of its people.

The Trappist-1 stellar system is home to seven Earth-like planets, and one of them could harbor life; rival teams of visionary pioneers use data to extrapolate entire worlds, leading the search for life on other planets throughout the universe.

The four categories of cute in the animal kingdom and the scientific stories behind why animals are cute.

The anticipation of the annual Great Migration is being felt by all of the Serengeti's families as they wait with great desperation for it to arrive; the land continues to get hotter and hunger starts to bite as food becomes even more scarce.

The long-awaited arrival of the Great Migration brings opportunities and food in abundance, but it also increases conflict as every one of the Serengeti's families is put to the test.

The dry season is now upon the animals of the Serengeti, turning the waterhole into a death trap for the herds, but for some this season is a gift.

It's time to close another chapter in the lives of the animals of the Serengeti; first, all around is a blackened wasteland, the aftermath of the huge fire.

In summer's home stretch, family ties run deep; Cole hunts for protein in the rain; Jessie gathers the last of the warm weather bounty; the Hailstones track shy prey; Ricko's legacy project.

Winter is the greatest test for life in the polar regions; in the Arctic, a female polar bear treks into the mountains to give birth; out on the frozen ocean, the entire population of the world's spectacled eider ducks braves the winter.

Brian takes a fresh look at the astonishing concept of gravity.

Exploring an unmapped volcanic underworld in search of the longest lava tube in Arabia.

Winter is the greatest test for life in the polar regions; in the Arctic, a female polar bear treks into the mountains to give birth; out on the frozen ocean, the entire population of the world's spectacled eider ducks braves the winter.

Brian takes a fresh look at the astonishing concept of gravity.

Exploring an unmapped volcanic underworld in search of the longest lava tube in Arabia.

Winter is the greatest test for life in the polar regions; in the Arctic, a female polar bear treks into the mountains to give birth; out on the frozen ocean, the entire population of the world's spectacled eider ducks braves the winter.

The Trappist-1 stellar system is home to seven Earth-like planets, and one of them could harbor life; rival teams of visionary pioneers use data to extrapolate entire worlds, leading the search for life on other planets throughout the universe.

Challenging the concept of reality with new data from a supermassive black hole.

Dr. Helen Czerski reveals how the harnessing of heat's power to transform matter has led to some of humanity's greatest achievements, from molten metal that enabled us to make tools to the searing heat of plasmas that offer near unlimited power.

With less than a month left in the fishing season, all crews are desperate to catch their remaining quota, and failing to do so means leaving money on the table; Justin and Mike are fighting to hit their target.

The adventurers move to a processing camp in an attempt to maximize the areas resources.

When the beaver pelts go missing, the group's only source of food is beaver jerky; Michela takes on too much maintaining the trap lines.

From bagels and poutine to beavers and ice hockey, Griff Rhys Jones explores Quebec to learn how French Canada really is; he reveals how its history and diversity have helped to shape la belle province and the multicultural Canada of present times.

With less than a month left in the fishing season, all crews are desperate to catch their remaining quota, and failing to do so means leaving money on the table; Justin and Mike are fighting to hit their target.

The adventurers move to a processing camp in an attempt to maximize the areas resources.

When the beaver pelts go missing, the group's only source of food is beaver jerky; Michela takes on too much maintaining the trap lines.

From bagels and poutine to beavers and ice hockey, Griff Rhys Jones explores Quebec to learn how French Canada really is; he reveals how its history and diversity have helped to shape la belle province and the multicultural Canada of present times.

In summer's home stretch, family ties run deep; Cole hunts for protein in the rain; Jessie gathers the last of the warm weather bounty; the Hailstones track shy prey; Ricko's legacy project.

The Trappist-1 stellar system is home to seven Earth-like planets, and one of them could harbor life; rival teams of visionary pioneers use data to extrapolate entire worlds, leading the search for life on other planets throughout the universe.

Challenging the concept of reality with new data from a supermassive black hole.

Levison and Alberto travel through Guatemala, Honduras and Nicaragua.

Levison and Alberto visit the landscapes, colonial cities, active volcanoes and mountains of Nicaragua and Costa Rica.

A Spinosaurus, the world's largest ever predatory dinosaur, struggles to bring up his babies and lead his young family across one of the deadliest environments on Earth.

A race to find the planet's 60 deadliest creatures.

Steve is in search of bait balls; these wildlife events can be seen from space, but they are not easy to find.

The four categories of cute in the animal kingdom and the scientific stories behind why animals are cute.

It's time to close another chapter in the lives of the animals of the Serengeti; first, all around is a blackened wasteland, the aftermath of the huge fire.

Professor Brian Cox traces the development of the four rocky worlds closest to the sun: Mercury, Venus, Earth and Mars; born together, they battled the unbelievable violence of the early solar system to become stable planets.

Without volcanoes, life on Earth would never have begun; they are responsible for both the planet's breathable atmosphere and the oceans; mineral-rich ash from regular eruptions fertilize the land.

It's time to close another chapter in the lives of the animals of the Serengeti; first, all around is a blackened wasteland, the aftermath of the huge fire.

Professor Brian Cox traces the development of the four rocky worlds closest to the sun: Mercury, Venus, Earth and Mars; born together, they battled the unbelievable violence of the early solar system to become stable planets.

Without volcanoes, life on Earth would never have begun; they are responsible for both the planet's breathable atmosphere and the oceans; mineral-rich ash from regular eruptions fertilize the land.

Professor Brian Cox traces the development of the four rocky worlds closest to the sun: Mercury, Venus, Earth and Mars; born together, they battled the unbelievable violence of the early solar system to become stable planets.

Alaskans prepare for the winter months; Andy hunts moose; Sue heads to Fairbanks for a foot procedure; the hailstones teach their daughters to ice fish; Glenn repairs his cabin.

Sue travels 150 miles to investigate squatters on her property; Andy's sled begins to fall apart while he's collecting firewood; Chip and Agnes brave thin ice to harvest whitefish.

Chip builds a freight sled for winter travel; Sue is forced to brave a dangerous road to get home after a blizzard strands her in Fairbanks; Andy and Kate get their sled dogs ready for winter; Glenn tries to harvest meat for the winter.

Gators, tortoises and stunning seabirds of southwest Florida.

Strange aquatic mammals populating a river in Columbia; a ship marooned in a sea of sand along Namibia's notorious Skeleton Coast; a Boeing 727 jetliner hidden in a pine forest; an unusual pattern is discovered in the Nevada desert.

The differences between the Northern and Southern Rockies.

Gators, tortoises and stunning seabirds of southwest Florida.

Strange aquatic mammals populating a river in Columbia; a ship marooned in a sea of sand along Namibia's notorious Skeleton Coast; a Boeing 727 jetliner hidden in a pine forest; an unusual pattern is discovered in the Nevada desert.

Scientists postulate that Earth was once sheathed in ice and complex animals evolved when the planet thawed, due to the release of carbon dioxide.

Gators, tortoises and stunning seabirds of southwest Florida.

A hundred days without sunlight approach; Glenn needs to retrieve more wood for heat; Andy and Kate rescue a bear cub; the Hailstones gather resources for themselves and their neighbors; Sue has a long list to complete.

Hannah goes behind the scenes to look at the technology behind the lift; along the way, she finds out how coal mines made lifts safer, gets to grips with a piece of medieval siege technology and discovers how a PR stunt changed the modern skyline.

In the remote reaches of Asia's frozen north, creatures must overcome unique challenges, finding exceptional ways to thrive in a hostile world that pushes life to its very limits.

Gators, tortoises and stunning seabirds of southwest Florida.

Exploring an unmapped volcanic underworld in search of the longest lava tube in Arabia.

A hundred days without sunlight approach; Glenn needs to retrieve more wood for heat; Andy and Kate rescue a bear cub; the Hailstones gather resources for themselves and their neighbors; Sue has a long list to complete.

After being raised on the ice in winter, emperor penguin chicks find themselves abandoned by their parents in spring; to survive, they must find their own way across the treacherous sea ice to the rich waters of the Southern Ocean.

In the aftermath of a devastating bushfire season, Zac and Darin learn about efforts to rehabilitate the wildlife and livestock population.

Levison and Alberto explore a vampire bat-infested cave, the Panama Canal and modern Panama City.

Levison begins his journey in Afghanistan's remote and inhospitable Wakhan Corridor.

In the aftermath of a devastating bushfire season, Zac and Darin learn about efforts to rehabilitate the wildlife and livestock population.

Levison and Alberto explore a vampire bat-infested cave, the Panama Canal and modern Panama City.

Levison begins his journey in Afghanistan's remote and inhospitable Wakhan Corridor.

A hundred days without sunlight approach; Glenn needs to retrieve more wood for heat; Andy and Kate rescue a bear cub; the Hailstones gather resources for themselves and their neighbors; Sue has a long list to complete.

Hannah goes behind the scenes to look at the technology behind the lift; along the way, she finds out how coal mines made lifts safer, gets to grips with a piece of medieval siege technology and discovers how a PR stunt changed the modern skyline.

After being raised on the ice in winter, emperor penguin chicks find themselves abandoned by their parents in spring; to survive, they must find their own way across the treacherous sea ice to the rich waters of the Southern Ocean.

A hundred days without sunlight approach; Glenn needs to retrieve more wood for heat; Andy and Kate rescue a bear cub; the Hailstones gather resources for themselves and their neighbors; Sue has a long list to complete.

Hope and Barry travel to Texas where not everyone agrees on how to help wildlife.

An enormous fiery vortex in Redding, California, the island nation of Malta loses a natural treasure, a mysterious radioactive hotspot is discovered near Chernobyl, and an unknown force lays waste to a mountain forest in Italian Alps.

Scientists postulate that Earth was once sheathed in ice and complex animals evolved when the planet thawed, due to the release of carbon dioxide.

Hope and Barry travel to Texas where not everyone agrees on how to help wildlife.

An enormous fiery vortex in Redding, California, the island nation of Malta loses a natural treasure, a mysterious radioactive hotspot is discovered near Chernobyl, and an unknown force lays waste to a mountain forest in Italian Alps.

Scientists postulate that Earth was once sheathed in ice and complex animals evolved when the planet thawed, due to the release of carbon dioxide.

Hope and Barry travel to Texas where not everyone agrees on how to help wildlife.

Dark winter brings new challenges in sub-zero temperatures; Andy maintains snow-covered trails; Sue fixes her generator; the Hailstones build a new teepee; Erik takes his wife hunting.

With scientists sending space probes to the furthest reaches of the solar system and beyond, the scientific search for alien life has begun; inspired by a childhood love of science fiction, Brian still hopes to hear from ET.

In the aftermath of a devastating bushfire season, Zac and Darin learn about efforts to rehabilitate the wildlife and livestock population.

Levison and Alberto explore a vampire bat-infested cave, the Panama Canal and modern Panama City.

Levison begins his journey in Afghanistan's remote and inhospitable Wakhan Corridor.

Dark winter brings new challenges in sub-zero temperatures; Andy maintains snow-covered trails; Sue fixes her generator; the Hailstones build a new teepee; Erik takes his wife hunting.

At the top of the planet lies the Arctic Ocean; after four months of winter darkness, the sun returns to reveal a frozen ocean covered in ice; mother polar bears emerge from their hillside dens and lead their cubs down to the sea ice to hunt.

A race to find the planet's 60 deadliest creatures.

Steve goes in search of the deadliest cats in Africa in the carnivore capital of Zambia; he gets up close to the rulers of the savanna, the lions and leopards.

Persued by a group of Utahraptors, a gang of armored dinosaurs battle to reach adulthood.

A race to find the planet's 60 deadliest creatures.

Steve goes in search of the deadliest cats in Africa in the carnivore capital of Zambia; he gets up close to the rulers of the savanna, the lions and leopards.

Persued by a group of Utahraptors, a gang of armored dinosaurs battle to reach adulthood.

Dark winter brings new challenges in sub-zero temperatures; Andy maintains snow-covered trails; Sue fixes her generator; the Hailstones build a new teepee; Erik takes his wife hunting.

With scientists sending space probes to the furthest reaches of the solar system and beyond, the scientific search for alien life has begun; inspired by a childhood love of science fiction, Brian still hopes to hear from ET.

At the top of the planet lies the Arctic Ocean; after four months of winter darkness, the sun returns to reveal a frozen ocean covered in ice; mother polar bears emerge from their hillside dens and lead their cubs down to the sea ice to hunt.

Dark winter brings new challenges in sub-zero temperatures; Andy maintains snow-covered trails; Sue fixes her generator; the Hailstones build a new teepee; Erik takes his wife hunting.

Traveling to San Diego, Hope and Allison look to learn how to handle huge caseloads and dangerous animals.

A long-forgotten network of Native American earthworks, a baffling battlefield mystery in Belgium, a mysterious blood red lake on a remote Greek island, and an eerie pink glow emulating form the middle of the Pacific Ocean.

Gros Morne National Park is the result of continental collision.

Traveling to San Diego, Hope and Allison look to learn how to handle huge caseloads and dangerous animals.

A long-forgotten network of Native American earthworks, a baffling battlefield mystery in Belgium, a mysterious blood red lake on a remote Greek island, and an eerie pink glow emulating form the middle of the Pacific Ocean.

Gros Morne National Park is the result of continental collision.

Traveling to San Diego, Hope and Allison look to learn how to handle huge caseloads and dangerous animals.

The Hailstones hide emergency supplies along their hunting and trapping routes; Sue's connection with the outside world hangs in the balance; Erik falls while gathering firewood.

Brian takes a fresh look at the astonishing concept of gravity.

A race to find the planet's 60 deadliest creatures.

Steve goes in search of the deadliest cats in Africa in the carnivore capital of Zambia; he gets up close to the rulers of the savanna, the lions and leopards.

Persued by a group of Utahraptors, a gang of armored dinosaurs battle to reach adulthood.

The Hailstones hide emergency supplies along their hunting and trapping routes; Sue's connection with the outside world hangs in the balance; Erik falls while gathering firewood.

Found on every continent, mountains create unique frozen worlds, home to extraordinary animals that must overcome the crushing conditions of the cold.

Tiger cubs that are only a few days old are prey for almost anything; hidden cameras follow the lives of tiger cubs growing up in India's jungle.

How wildlife adapts for survival to the seasonal shifts in the sun's intensity, from wood frogs that can freeze and thaw to Arctic wolves that thrive in the chilly darkness.

Wonders created by life itself include the Amazon and a father and son brave killer bees in Bangladesh.

Tiger cubs that are only a few days old are prey for almost anything; hidden cameras follow the lives of tiger cubs growing up in India's jungle.

How wildlife adapts for survival to the seasonal shifts in the sun's intensity, from wood frogs that can freeze and thaw to Arctic wolves that thrive in the chilly darkness.

Wonders created by life itself include the Amazon and a father and son brave killer bees in Bangladesh.

The Hailstones hide emergency supplies along their hunting and trapping routes; Sue's connection with the outside world hangs in the balance; Erik falls while gathering firewood.

Brian takes a fresh look at the astonishing concept of gravity.

Found on every continent, mountains create unique frozen worlds, home to extraordinary animals that must overcome the crushing conditions of the cold.

The Hailstones hide emergency supplies along their hunting and trapping routes; Sue's connection with the outside world hangs in the balance; Erik falls while gathering firewood.

Incredible stories of wildlife rescue and rehabilitation.

Dive into the historical and natural secrets of the deep; explore an uninhabited concrete island, ocean spirals off the Australian coast, underwater evidence of a violent past and tracks thousands of metres below the sea's surface.

The crew explores the Atacama Desert, the world's driest non-polar region.

Incredible stories of wildlife rescue and rehabilitation.

Dive into the historical and natural secrets of the deep; explore an uninhabited concrete island, ocean spirals off the Australian coast, underwater evidence of a violent past and tracks thousands of metres below the sea's surface.

The crew explores the Atacama Desert, the world's driest non-polar region.

Incredible stories of wildlife rescue and rehabilitation.

Chip and Agnes head to Kiwalik River for hunting and fishing; Sue fabricates snowshoes to scout the tundra; Andy fights through frigid temperatures to replenish his resources; Erik and Martha set fur traps.

Brian explores one of the greatest mysteries in physics: time.

Tiger cubs that are only a few days old are prey for almost anything; hidden cameras follow the lives of tiger cubs growing up in India's jungle.

How wildlife adapts for survival to the seasonal shifts in the sun's intensity, from wood frogs that can freeze and thaw to Arctic wolves that thrive in the chilly darkness.

Wonders created by life itself include the Amazon and a father and son brave killer bees in Bangladesh.

Chip and Agnes head to Kiwalik River for hunting and fishing; Sue fabricates snowshoes to scout the tundra; Andy fights through frigid temperatures to replenish his resources; Erik and Martha set fur traps.

Persued by a group of Utahraptors, a gang of armored dinosaurs battle to reach adulthood.

With summer nearing its end, Alaskans kick into high gear.

Frightening ice conditions and poor weather make the early season treacherous; Justin and Mike experience a violent ice-quake that leaves them rattled; Trevor contends with other fishermen setting their nets too close to his.

Levison and Alberto explore a vampire bat-infested cave, the Panama Canal and modern Panama City.

With summer nearing its end, Alaskans kick into high gear.

Frightening ice conditions and poor weather make the early season treacherous; Justin and Mike experience a violent ice-quake that leaves them rattled; Trevor contends with other fishermen setting their nets too close to his.

Levison and Alberto explore a vampire bat-infested cave, the Panama Canal and modern Panama City.

Chip and Agnes head to Kiwalik River for hunting and fishing; Sue fabricates snowshoes to scout the tundra; Andy fights through frigid temperatures to replenish his resources; Erik and Martha set fur traps.

Brian explores one of the greatest mysteries in physics: time.

Frightening ice conditions and poor weather make the early season treacherous; Justin and Mike experience a violent ice-quake that leaves them rattled; Trevor contends with other fishermen setting their nets too close to his.

Chip and Agnes head to Kiwalik River for hunting and fishing; Sue fabricates snowshoes to scout the tundra; Andy fights through frigid temperatures to replenish his resources; Erik and Martha set fur traps.

It is Hope's open house and with it brings incredible releases; Hope hears news that will change everything.

Traipsing along ancient pathways criss-crossing Easter Island; finding gigantic designs carved into Asia's Eastern Steppe; ascending a tall pyramid rising from Antarctica's icy landscape.

A feature on the Andean Altiplano, a rugged plain in Bolivia.

It is Hope's open house and with it brings incredible releases; Hope hears news that will change everything.

Traipsing along ancient pathways criss-crossing Easter Island; finding gigantic designs carved into Asia's Eastern Steppe; ascending a tall pyramid rising from Antarctica's icy landscape.

A feature on the Andean Altiplano, a rugged plain in Bolivia.

It is Hope's open house and with it brings incredible releases; Hope hears news that will change everything.

Andy makes snares; Erik and Martha cut into their last moose quarter; Chip and Agnus hunt caribou; Sue clears the plane runway for her snow machine delivery.

Brian questions how far humans will go in their exploration of the cosmos.

With summer nearing its end, Alaskans kick into high gear.

Frightening ice conditions and poor weather make the early season treacherous; Justin and Mike experience a violent ice-quake that leaves them rattled; Trevor contends with other fishermen setting their nets too close to his.

Levison and Alberto explore a vampire bat-infested cave, the Panama Canal and modern Panama City.

Andy makes snares; Erik and Martha cut into their last moose quarter; Chip and Agnus hunt caribou; Sue clears the plane runway for her snow machine delivery.

Trekking across the planet's most hostile frozen zone: Antarctica; getting to know ice.

The incredible story of how Pluto has been propelled from an unremarkable ball of ice on the edge of the solar system to a world of unimaginable complexity; one where some form of alien life might even exist.

Asking questions about the universe and how it came to be 13.8 billion years ago; inspecting images gathered by the Hubble and Planck space telescopes and clues that are giving scientists insight into the origins of life.

The incredible story of how Pluto has been propelled from an unremarkable ball of ice on the edge of the solar system to a world of unimaginable complexity; one where some form of alien life might even exist.

Asking questions about the universe and how it came to be 13.8 billion years ago; inspecting images gathered by the Hubble and Planck space telescopes and clues that are giving scientists insight into the origins of life.

Andy makes snares; Erik and Martha cut into their last moose quarter; Chip and Agnus hunt caribou; Sue clears the plane runway for her snow machine delivery.

Brian questions how far humans will go in their exploration of the cosmos.

Trekking across the planet's most hostile frozen zone: Antarctica; getting to know ice.

Andy makes snares; Erik and Martha cut into their last moose quarter; Chip and Agnus hunt caribou; Sue clears the plane runway for her snow machine delivery.

A journey on Scotland's River Spey, traveling from its source in the Highlands, winding by boat through the mountains to where the river meets the North Sea.

The differences between the Northern and Southern Rockies.

Strange aquatic mammals populating a river in Columbia; a ship marooned in a sea of sand along Namibia's notorious Skeleton Coast; a Boeing 727 jetliner hidden in a pine forest; an unusual pattern is discovered in the Nevada desert.

A journey on Scotland's River Spey, traveling from its source in the Highlands, winding by boat through the mountains to where the river meets the North Sea.

Gros Morne National Park is the result of continental collision.

A long-forgotten network of Native American earthworks, a baffling battlefield mystery in Belgium, a mysterious blood red lake on a remote Greek island, and an eerie pink glow emulating form the middle of the Pacific Ocean.

A journey on Scotland's River Spey, traveling from its source in the Highlands, winding by boat through the mountains to where the river meets the North Sea.

Tiger cubs that are only a few days old are prey for almost anything; hidden cameras follow the lives of tiger cubs growing up in India's jungle.

After being raised on the ice in winter, emperor penguin chicks find themselves abandoned by their parents in spring; to survive, they must find their own way across the treacherous sea ice to the rich waters of the Southern Ocean.

At the top of the planet lies the Arctic Ocean; after four months of winter darkness, the sun returns to reveal a frozen ocean covered in ice; mother polar bears emerge from their hillside dens and lead their cubs down to the sea ice to hunt.

Found on every continent, mountains create unique frozen worlds, home to extraordinary animals that must overcome the crushing conditions of the cold.

Trekking across the planet's most hostile frozen zone: Antarctica; getting to know ice.