The Lurking Menace: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 3).

The Constellation Code: Experts check out structures built to mirror the constellations. Could they have been built as a message to extraterrestrials? (S12, ep 13).

Nuclear Agenda: Ever since the first atomic bomb went off in 1945, UFOs have been spotted at nuclear facilities across the world. Could this signal a threat to mankind? (S12, ep 14).

Forgotten Greenland Ghost Town: Mysterious industrial waste is discovered in an uninhabited part of Greenland. Meanwhile, strange mounds are found deep within the Arctic Circle. (S3, ep 7).

B24: The Liberator proved its worth in WWII over Europe and the Pacific, modeled after the B-17, delivering blows to the Axis. (S2, ep 4).

Embark on an eye-opening journey as experts investigate the startling mysteries captured by satellites orbiting the Earth: from hidden worlds to unexplainable natural phenomena. (S4, ep 18).

The Constellation Code: Experts check out structures built to mirror the constellations. Could they have been built as a message to extraterrestrials? (S12, ep 13).

Nuclear Agenda: Ever since the first atomic bomb went off in 1945, UFOs have been spotted at nuclear facilities across the world. Could this signal a threat to mankind? (S12, ep 14).

Rome's Rise and Fall: Did our ancestors believe they were cursed? Professor Alice Roberts explores historic cataclysmic events through a scientific lens to dispel the myths. (2 of 5).

Carrickfergus: Dan visits one of Northern Ireland's oldest castles, Carrickfergus, to learn more about the tempestuous relationship between Britain and Ireland. (S1, ep 6).

Angkor Wat: The story behind the breath-taking temple complex, which is located in Cambodia and is the largest religious monument in the world.

B24: The Liberator proved its worth in WWII over Europe and the Pacific, modeled after the B-17, delivering blows to the Axis. (S2, ep 4).

The Ghost in the Machine: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 4).

Visit a luxury survival condo in Kansas, a minefield in Sarajevo and the King Cobra Village in Thailand. Elsewhere, explore the \"fake\" pentagon on the outskirts of Shanghai. (S1, ep 2).

Experts investigate evidence suggesting that aliens have created the means for controlling humanity. They find that the shocking truth might be hidden right inside you. (S1, ep 9).

The Right Tools: Victory in war doesn't just require sound military strategy, vital resources and equipment are also critical. Discover how the Axis powers failed in this regard. (S1, ep 4).

Society: Explore the theme of society and myths that engulf memories of the past. These myths often become woven into the fabric of our society and can pass through generations. (S1, ep 4).

Forgotten Greenland Ghost Town: Mysterious industrial waste is discovered in an uninhabited part of Greenland. Meanwhile, strange mounds are found deep within the Arctic Circle. (S3, ep 7).

Archaeologists investigate the full story of how the most famous Roman leader, Julius Caesar, rose to power and the battle that took him to the brink of defeat. (1 of 2).

The Constellation Code: Experts check out structures built to mirror the constellations. Could they have been built as a message to extraterrestrials? (S12, ep 13).

Nuclear Agenda: Ever since the first atomic bomb went off in 1945, UFOs have been spotted at nuclear facilities across the world. Could this signal a threat to mankind? (S12, ep 14).

Carrickfergus: Dan visits one of Northern Ireland's oldest castles, Carrickfergus, to learn more about the tempestuous relationship between Britain and Ireland. (S1, ep 6).

Extreme Engineering: How did the ancients get oil from the ground without modern drills? And build a bridge across the Rhine in just 10 days? Experts investigate. (S1, ep 10).

Experts investigate evidence suggesting that aliens have created the means for controlling humanity. They find that the shocking truth might be hidden right inside you. (S1, ep 9).

The Ghost in the Machine: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 4).

The Alien Mountain: Experts investigate an Italian mountain that's stood witness to inexplicable phenomena for centuries. Could it somehow be attracting alien visitors? (S12, ep 15).

The Secrets of Stonehenge: A DNA study released in 2018 revealed that the original builders of Stonehenge mysteriously vanished - did they head back to a home among the stars? (S12, ep 16).

Abandoned Alpine Fortress: A group of hikers trekking across the Italian Alps stumble upon abandoned military infrastructure. What purpose did these camouflaged buildings serve? (S3, ep 8).

Skyraider: The many variants of this single piston engine fighter bomber helped dominate the air to ground attack role in Vietnam, earning quite a reputation. (S2, ep 5).

Embark on an eye-opening journey as experts investigate the startling mysteries captured by satellites orbiting the Earth: from hidden worlds to unexplainable natural phenomena. (S4, ep 19).

The Alien Mountain: Experts investigate an Italian mountain that's stood witness to inexplicable phenomena for centuries. Could it somehow be attracting alien visitors? (S12, ep 15).

The Secrets of Stonehenge: A DNA study released in 2018 revealed that the original builders of Stonehenge mysteriously vanished - did they head back to a home among the stars? (S12, ep 16).

The Darkest Age: Did our ancestors believe they were cursed? Professor Alice Roberts explores historic cataclysmic events such as wars and floods to dispel the myths. (3 of 5).

Edinburgh: A look at one of Scotland's most popular paid tourist attraction. With a slew of sieges to its name, it is no surprise that the site boasts some formidable defences. (1 of 5).

Hagia Sophia Of Istanbul: Built in 537, this is a walk-through the stunning place of worship located in Istanbul, Turkey.

Skyraider: The many variants of this single piston engine fighter bomber helped dominate the air to ground attack role in Vietnam, earning quite a reputation. (S2, ep 5).

Oblivion Calling: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 5).

Learn about Togo's traditional religious practices and take a tour of the incredible Danakil Desert in Ethiopia. Plus, visit a city in Georgia where every citizen has a gun. (S1, ep 3).

Could Hitler's crazed quest for world domination have been influenced by aliens? Experts reveal the extraterrestrial secret Hitler may have been hiding and where it is now. (S1, ep 10).

The Sobibor Revolt: During World War II, the Nazi war machine creates specialised death camps. At Sobibor, Poland, a small number of Jews engineer a mass escape. (S2, ep 4).

The Birth of Mickey: Recount the birth of Mickey Mouse, from being created as a pencil sketch to rocketing into untouchable, lasting fame. (S1, ep 1).

Abandoned Alpine Fortress: A group of hikers trekking across the Italian Alps stumble upon abandoned military infrastructure. What purpose did these camouflaged buildings serve? (S3, ep 8).

Zeus: Ancient Greece's most powerful god wages an epic struggle against his father for control of the universe. It's the ultimate clash in what is mythology's greatest showdown. (S1, ep 10).

The Alien Mountain: Experts investigate an Italian mountain that's stood witness to inexplicable phenomena for centuries. Could it somehow be attracting alien visitors? (S12, ep 15).

The Secrets of Stonehenge: A DNA study released in 2018 revealed that the original builders of Stonehenge mysteriously vanished - did they head back to a home among the stars? (S12, ep 16).

Edinburgh: A look at one of Scotland's most popular paid tourist attraction. With a slew of sieges to its name, it is no surprise that the site boasts some formidable defences. (1 of 5).

Angkor Wat: The story behind the breath-taking temple complex, which is located in Cambodia and is the largest religious monument in the world.

Could Hitler's crazed quest for world domination have been influenced by aliens? Experts reveal the extraterrestrial secret Hitler may have been hiding and where it is now. (S1, ep 10).

Oblivion Calling: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 5).

Telepathy: Could aliens have given our brains incredible untapped abilities? Experts ask whether harnessing these hidden powers could spark the next step in our evolution. (S12, ep 17).

Food of the Gods: Experts question the link between divine substances and extraterrestrials. Could the food of the gods really have been sustaining Earth's alien visitors? (S12, ep 18).

Long Lost Arctic Army Base: A secret military base is discovered a few hundred miles from the North Pole, while a man-made stone formation is found 120-feet below Lake Huron. (S3, ep 9).

Huey: The definitive combat helicopter debuted in Southeast Asia, serving as transport, gunship, smoke ship, command center, MediVac and many other roles. (S2, ep 6).

Embark on an eye-opening journey as experts investigate the startling mysteries captured by satellites orbiting the Earth: from hidden worlds to unexplainable natural phenomena. (S4, ep 20).

Telepathy: Could aliens have given our brains incredible untapped abilities? Experts ask whether harnessing these hidden powers could spark the next step in our evolution. (S12, ep 17).

Food of the Gods: Experts question the link between divine substances and extraterrestrials. Could the food of the gods really have been sustaining Earth's alien visitors? (S12, ep 18).

God's Holy Warriors: Did our ancestors believe they were cursed? Professor Alice Roberts explores historic cataclysmic events such as wars and floods to dispel the myths. (4 of 5).

Cardiff: Dan Jones explores the history of Cardiff castle over more than 2,000 years and reveals how it transformed into a lavish Victorian home. (2 of 5).

Le Louvre: A look at the world's largest art museum, located in Paris, France and the home of the Mona Lisa.

Huey: The definitive combat helicopter debuted in Southeast Asia, serving as transport, gunship, smoke ship, command center, MediVac and many other roles. (S2, ep 6).

Origin Unknown: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 6).

Visit some of the world's most unusual houses, explore the Bangladeshi city with the largest number of cycle rickshaws and travel to the richest village in all of China. (S1, ep 4).

Experts unseal the truth about the potential aliens living and working among us. Who has come in peace? And who has a more sinister motive in mind? (S1, ep 11).

Part Two: Through archive footage, see how these radically different characters clashed in a fascinating subplot of World War II. (2 of 2).

Mystifying Cursed Objects: Ancient cultures around the world have aroused fascination and provoked fear with curses and objects used to conjure them. (S1, ep 8).

Long Lost Arctic Army Base: A secret military base is discovered a few hundred miles from the North Pole, while a man-made stone formation is found 120-feet below Lake Huron. (S3, ep 9).

The Beast Master: Enslaved by the Romans, Carpophorus gets trained to fight beasts in the Colosseum for the public's amusement. (S1, ep 3).

Telepathy: Could aliens have given our brains incredible untapped abilities? Experts ask whether harnessing these hidden powers could spark the next step in our evolution. (S12, ep 17).

Food of the Gods: Experts question the link between divine substances and extraterrestrials. Could the food of the gods really have been sustaining Earth's alien visitors? (S12, ep 18).

Cardiff: Dan Jones explores the history of Cardiff castle over more than 2,000 years and reveals how it transformed into a lavish Victorian home. (2 of 5).

Hagia Sophia Of Istanbul: Built in 537, this is a walk-through the stunning place of worship located in Istanbul, Turkey.

Experts unseal the truth about the potential aliens living and working among us. Who has come in peace? And who has a more sinister motive in mind? (S1, ep 11).

Origin Unknown: From ghostly voices to vanishing UFOs, experts investigate puzzling and mysterious signal interferences and break down the meanings behind them. (S1, ep 6).

Human Hieroglyphs: Tattoos, piercings and body modifications are big business. But could our desire for these changes stem from a profound link to our ancestors? (S12, ep 19).

The Mystery of Skinwalker: Nestled in Utah lies a ranch some believe to be a hotbed of strange phenomena. Is it all connected to an alien entity known as the Skinwalker? (S12, ep 21).

WWII Warship Wreckage: A giant naval vessel is located on the bottom of the Norwegian Sea, while an ancient reptile-like creature is found in Canada. (S3, ep 10).

Avenger: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 1).

Embark on an eye-opening journey as experts investigate the startling mysteries captured by satellites orbiting the Earth: from hidden worlds to unexplainable natural phenomena. (S4, ep 1).

Aliens And The Lost Ark: Experts on the extraterrestrial investigate the possibility of the religious relic being an alien artefact. (S1, ep 7).

Human Hieroglyphs: Tattoos, piercings and body modifications are big business. But could our desire for these changes stem from a profound link to our ancestors? (S12, ep 19).

Medieval Mystery: Did our ancestors believe they were cursed? Professor Alice Roberts explores historic cataclysmic events such as wars and floods to dispel the myths. (5 of 5).

York: Dan explores the history of York's castle, from the Viking Jorvik and the Normans, to the dark days of the anti-Jewish pogrom and the imprisonment of the Knights Templar. (3 of 5).

Taj Mahal: A walk through the iconic mausoleum complex, located in India and commissioned in 1632 by the Mughal emperor Shah Jahan to house the remains of his beloved wife.

Avenger: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 1).

Journey to an Indian village where men train to become bouncers in the big city. Elsewhere, take a tour of the Chinese settlement where fire erupts from the ground. (S1, ep 1).

Meet the man who paints cliffs bright green and explore Zimbabwe's abandoned places. Plus, visit India's largest vegetable market and a truly unique village in China. (S1, ep 5).

Experts investigate the mystery of the Solway Firth Spaceman - a spacesuit-clad figure who strangely appeared in a photograph taken in Cumbria. (S1, ep 12).

The Pierre Hotel Robbery: Two skilled thieves go after New York's Pierre Hotel. The team take over the hotel, getting into the lobby vault and hundreds of safe deposit boxes. (S1, ep 3).

The Brotherhood Is a Lie: Charles Peewee Goldsmith wanted nothing more than to be a Hells Angel. He fought to become a president, only for the Angels to turn on him. (S1, ep 4).

WWII Warship Wreckage: A giant naval vessel is located on the bottom of the Norwegian Sea, while an ancient reptile-like creature is found in Canada. (S3, ep 10).

Cleopatra: The enigmatic Egyptian Queen's untold story is one of a ruthless genius, doing anything necessary to cling to power in the face of an ever-expanding Roman Empire. (S1, ep 3).

Human Hieroglyphs: Tattoos, piercings and body modifications are big business. But could our desire for these changes stem from a profound link to our ancestors? (S12, ep 19).

York: Dan explores the history of York's castle, from the Viking Jorvik and the Normans, to the dark days of the anti-Jewish pogrom and the imprisonment of the Knights Templar. (3 of 5).

Le Louvre: A look at the world's largest art museum, located in Paris, France and the home of the Mona Lisa.

Experts investigate the mystery of the Solway Firth Spaceman - a spacesuit-clad figure who strangely appeared in a photograph taken in Cumbria. (S1, ep 12).

Journey to an Indian village where men train to become bouncers in the big city. Elsewhere, take a tour of the Chinese settlement where fire erupts from the ground. (S1, ep 1).

The Pharaohs' Curse: Could a curse really exist on Tutankhamun's tomb, but in the form of alien technology designed to protect an incredible secret about our past? (S10, ep 4).

The Science Wars: Examining claims that extraordinary discoveries are being ignored by the scientific community for not conforming to their accepted paradigm. (S10, ep 5).

City of the Gods: The ancient metropolis of Teotihuacan, called The City of The Gods by the Aztecs, is a site of great mystery. Could alien beings have once lived there? (S10, ep 6).

Stirling: Stirling has long been one of the most strategically important castles in Britain. Dan Jones examines the rich and savage history of this stronghold. (S1, ep 5).

Carrickfergus: Dan visits one of Northern Ireland's oldest castles, Carrickfergus, to learn more about the tempestuous relationship between Britain and Ireland. (S1, ep 6).

Edinburgh: A look at one of Scotland's most popular paid tourist attraction. With a slew of sieges to its name, it is no surprise that the site boasts some formidable defences. (1 of 5).

The Pharaohs' Curse: Could a curse really exist on Tutankhamun's tomb, but in the form of alien technology designed to protect an incredible secret about our past? (S10, ep 4).

The Science Wars: Examining claims that extraordinary discoveries are being ignored by the scientific community for not conforming to their accepted paradigm. (S10, ep 5).

Journey to an Indian village where men train to become bouncers in the big city. Elsewhere, take a tour of the Chinese settlement where fire erupts from the ground. (S1, ep 1).

The Right Tools: Victory in war doesn't just require sound military strategy, vital resources and equipment are also critical. Discover how the Axis powers failed in this regard. (S1, ep 4).

Churchill Strikes Back: December 1941: Under cover of a fierce naval bombardment, a taskforce of elite British commandos sail towards the Norwegian town of South Vaagso. (S1, ep 4).

The Troubling Tale of Bute Inlet Gold Pt. 1: The search for Slumach's gold sends the team 300 kilometres away into the heart of the mystery. (S1, ep 6).

The Birth of Mickey: Recount the birth of Mickey Mouse, from being created as a pencil sketch to rocketing into untouchable, lasting fame. (S1, ep 1).

Panzer Pals: Hans Jochaim-Horn breaks into a German army base, steals a tank and smashes through three sets of gates at Schwalmstadt Prison to breakout his friend. (S1, ep 10).

Society: Explore the theme of society and myths that engulf memories of the past. These myths often become woven into the fabric of our society and can pass through generations. (S1, ep 4).

The Beast Master: Enslaved by the Romans, Carpophorus gets trained to fight beasts in the Colosseum for the public's amusement. (S1, ep 3).

Zeus: Ancient Greece's most powerful god wages an epic struggle against his father for control of the universe. It's the ultimate clash in what is mythology's greatest showdown. (S1, ep 10).

The Pharaohs' Curse: Could a curse really exist on Tutankhamun's tomb, but in the form of alien technology designed to protect an incredible secret about our past? (S10, ep 4).

The Science Wars: Examining claims that extraordinary discoveries are being ignored by the scientific community for not conforming to their accepted paradigm. (S10, ep 5).

City of the Gods: The ancient metropolis of Teotihuacan, called The City of The Gods by the Aztecs, is a site of great mystery. Could alien beings have once lived there? (S10, ep 6).

Zeus: Ancient Greece's most powerful god wages an epic struggle against his father for control of the universe. It's the ultimate clash in what is mythology's greatest showdown. (S1, ep 10).

Carrickfergus: Dan visits one of Northern Ireland's oldest castles, Carrickfergus, to learn more about the tempestuous relationship between Britain and Ireland. (S1, ep 6).

Edinburgh: A look at one of Scotland's most popular paid tourist attraction. With a slew of sieges to its name, it is no surprise that the site boasts some formidable defences. (1 of 5).

The Right Tools: Victory in war doesn't just require sound military strategy, vital resources and equipment are also critical. Discover how the Axis powers failed in this regard. (S1, ep 4).

The Alien Frequency: Different cultures have used mantras and chanting for thousands of years - could these in fact be a method of communing with extraterrestrial forces? (S10, ep 7).

The Majestic Twelve: Did a top secret group of officials, dubbed the Majestic Twelve, really create a space programme that has already established bases on the moon? (S10, ep 8).

The Akashic Record: Experts question if Cloud computing represents the rediscovery of an ancient repository of knowledge known as the Akashic Record. (S10, ep 9).

George III - More Than His Madness: George III, the first Georgian King born in Britain, faces the American Revolution and family scandals. (S1, ep 3).

The race to develop the first atomic bomb was critical amid the struggle for WWII victory. Experts reveal new evidence behind Germany's top-secret development of nuclear weapons. (S1, ep 1).

The Pierre Hotel Robbery: Two skilled thieves go after New York's Pierre Hotel. The team take over the hotel, getting into the lobby vault and hundreds of safe deposit boxes. (S1, ep 3).

Visit a luxury survival condo in Kansas, a minefield in Sarajevo and the King Cobra Village in Thailand. Elsewhere, explore the \"fake\" pentagon on the outskirts of Shanghai. (S1, ep 2).

Learn about Togo's traditional religious practices and take a tour of the incredible Danakil Desert in Ethiopia. Plus, visit a city in Georgia where every citizen has a gun. (S1, ep 3).

Visit some of the world's most unusual houses, explore the Bangladeshi city with the largest number of cycle rickshaws and travel to the richest village in all of China. (S1, ep 4).

The Alien Frequency: Different cultures have used mantras and chanting for thousands of years - could these in fact be a method of communing with extraterrestrial forces? (S10, ep 7).

The Majestic Twelve: Did a top secret group of officials, dubbed the Majestic Twelve, really create a space programme that has already established bases on the moon? (S10, ep 8).

From December 1941 to May 1942, Singapore falls, the Wannsee Conference is held in Berlin and a single event in the Pacific transforms the war into a total global conflict.

Cardiff: Dan Jones explores the history of Cardiff castle over more than 2,000 years and reveals how it transformed into a lavish Victorian home. (2 of 5).

York: Dan explores the history of York's castle, from the Viking Jorvik and the Normans, to the dark days of the anti-Jewish pogrom and the imprisonment of the Knights Templar. (3 of 5).

The Akashic Record: Experts question if Cloud computing represents the rediscovery of an ancient repository of knowledge known as the Akashic Record. (S10, ep 9).

The Battle of Thermopylae: Journey back to 480 BC, when King Leonidas and his 300 Spartans successfully blocked Xerxes' two-million-strong Persian army at Thermopylae. (S1, ep 3).

Leaders: Venture back in time and explore the stories of some of history's most notable leaders, from Sir Winston Churchill to Fidel Castro and Nelson Mandela. (S1, ep 3).

The Alien Frequency: Different cultures have used mantras and chanting for thousands of years - could these in fact be a method of communing with extraterrestrial forces? (S10, ep 7).

The Majestic Twelve: Did a top secret group of officials, dubbed the Majestic Twelve, really create a space programme that has already established bases on the moon? (S10, ep 8).

The Akashic Record: Experts question if Cloud computing represents the rediscovery of an ancient repository of knowledge known as the Akashic Record. (S10, ep 9).

The Beast Master: Enslaved by the Romans, Carpophorus gets trained to fight beasts in the Colosseum for the public's amusement. (S1, ep 3).

Cardiff: Dan Jones explores the history of Cardiff castle over more than 2,000 years and reveals how it transformed into a lavish Victorian home. (2 of 5).

York: Dan explores the history of York's castle, from the Viking Jorvik and the Normans, to the dark days of the anti-Jewish pogrom and the imprisonment of the Knights Templar. (3 of 5).

Taj Mahal: A walk through the iconic mausoleum complex, located in India and commissioned in 1632 by the Mughal emperor Shah Jahan to house the remains of his beloved wife.

The Storming of Area 51: When millions responded to a call to storm Area 51, the US military vowed deadly force. Are they hiding the truth about extraterrestrials on Earth? (S12, ep 20).

Secrets of the Exoplanets: Over the past 20 years, thousands of potentially habitable exoplanets have been found. Could they be home to intelligent extraterrestrial life? (S12, ep 22).

The search for missing mountaineer Janet Mae Johnson, from 1973, gains momentum with the discovery of her backpack and camera in 2020. (S4, ep 1).

Ju52: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 2).

Journey to an Indian village where men train to become bouncers in the big city. Elsewhere, take a tour of the Chinese settlement where fire erupts from the ground. (S1, ep 1).

The Storming of Area 51: When millions responded to a call to storm Area 51, the US military vowed deadly force. Are they hiding the truth about extraterrestrials on Earth? (S12, ep 20).

Secrets of the Exoplanets: Over the past 20 years, thousands of potentially habitable exoplanets have been found. Could they be home to intelligent extraterrestrial life? (S12, ep 22).

From ancient Egypt - when the Pharaohs ruled - to Anglo-Saxon England, uncover the origins of the curses surrounding the Bust of Nefertiti, the Staffordshire Hoard and more. (S1, ep 1).

Leeds: Dan Jones explores the 900-year history of the beautiful Leeds Castle in Kent, from its origins as a royal Saxon family's manor to a 20th-century retreat for the rich. (4 of 6).

The Holy Sepulchre of Jerusalem: Uncover the secrets of the Holy Sepulchre, the sacred Christian site built in the same spot as the death and resurrection of Jesus. (S3, ep 1).

Ju52: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 2).

Military Mysteries: Discover an array of mysterious phenomena seen from above, including a Nazi weapon in Northern France and a Russian military tower near Chernobyl. (S1, ep 2).

Visit Italy's most fascinating ghost town, learn about an edible bird nest in Malaysia and explore the Bollate Prison. Plus, check out a structure dubbed the Dr Seuss House. (S1, ep 6).

Could history's most powerful men know more about extra-terrestrials than us? Experts explore the complex relationship between presidents and aliens. (S1, ep 13).

Ancient Global Warming: Did our ancestors believe they were cursed? Professor Alice Roberts explores historic cataclysmic events such as wars and floods to dispel the myths. (1 of 5).

The Kaiser Sunken Fleet: Ross Kemp continues his adventure in Scapa Flow, plunging down on the wrecks of a German warship and an experimental submarine aircraft called the M2. (S1, ep 2).

The search for missing mountaineer Janet Mae Johnson, from 1973, gains momentum with the discovery of her backpack and camera in 2020. (S4, ep 1).

The Battle of the Teutoburg Forest: Rome never recovered after Arminius' tactics in the Teutoburg Forest. Many of the associated riddles are answered, but some remain unresolved. (S1, ep 4).

The Storming of Area 51: When millions responded to a call to storm Area 51, the US military vowed deadly force. Are they hiding the truth about extraterrestrials on Earth? (S12, ep 20).

Secrets of the Exoplanets: Over the past 20 years, thousands of potentially habitable exoplanets have been found. Could they be home to intelligent extraterrestrial life? (S12, ep 22).

Leeds: Dan Jones explores the 900-year history of the beautiful Leeds Castle in Kent, from its origins as a royal Saxon family's manor to a 20th-century retreat for the rich. (4 of 6).

Taj Mahal: A walk through the iconic mausoleum complex, located in India and commissioned in 1632 by the Mughal emperor Shah Jahan to house the remains of his beloved wife.

Could history's most powerful men know more about extra-terrestrials than us? Experts explore the complex relationship between presidents and aliens. (S1, ep 13).

Military Mysteries: Discover an array of mysterious phenomena seen from above, including a Nazi weapon in Northern France and a Russian military tower near Chernobyl. (S1, ep 2).

The Mystery of Nan Madol: Giorgio A Tsoukalos and David Childress explore the mysterious chain of man-made islets in Micronesia's Nan Madol. Could local legends be true? (S12, ep 23).

The Relics of Roswell: In 1947, the US military collected debris of what they claimed was a crashed weather balloon outside Roswell, New Mexico. But was there more to it? (S12, ep 25).

In Siberia, a 44,000-year-old wolf, perfectly preserved in permafrost, may hold secrets about Ice Age bacteria and ancient microbial life. (S4, ep 2).

P47: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 3).

Visit a luxury survival condo in Kansas, a minefield in Sarajevo and the King Cobra Village in Thailand. Elsewhere, explore the \"fake\" pentagon on the outskirts of Shanghai. (S1, ep 2).

The Mystery of Nan Madol: Giorgio A Tsoukalos and David Childress explore the mysterious chain of man-made islets in Micronesia's Nan Madol. Could local legends be true? (S12, ep 23).

The Relics of Roswell: In 1947, the US military collected debris of what they claimed was a crashed weather balloon outside Roswell, New Mexico. But was there more to it? (S12, ep 25).

From medieval Britain to the Northwest Passage in the Arctic, uncover the origins of the curses surrounding the Stone of Destiny, Landseer's Man Proposes, God Disposes and more. (S1, ep 2).

Lancaster: Dan Jones visits Lancaster Castle to explore its grisly history of crime and punishment, including the infamous Lancashire Witches trials. (5 of 6).

Notre Dame of Paris: One of the world's most popular cathedrals, Notre Dame suffered a devastating fire in 2019 - but how is it surviving today? (S3, ep 2).

P47: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 3).

Submerged: A Turkish drought reveals a long-lost Basilica and its secrets, while the hull of a ship in the North Sea answers decades-old questions. (S1, ep 4).

Take a closer look at the working conditions of a miner in Indonesia, visit the Petrifying Well in England and tour a village where the houses are simply holes in the ground. (S1, ep 7).

Experts scrutinise the engineering behind the Egyptians' Sphinx and pyramids. Could this advanced civilisation have received extra-terrestrial help? (S1, ep 14).

The Homefront: In our final episode, we examine how each Axis Power had troubles on their own home front, leading to disaster in the final days of the war. (S1, ep 5).

Leaders & Legends: Explore the stories of the leaders and key figures who have defined periods of history and whose mythologies often outlive their influence. (S1, ep 5).

In Siberia, a 44,000-year-old wolf, perfectly preserved in permafrost, may hold secrets about Ice Age bacteria and ancient microbial life. (S4, ep 2).

Archaeologists investigate the full story of how the most famous Roman leader, Julius Caesar, rose to power and the battle that took him to the brink of defeat. (2 of 2).

The Mystery of Nan Madol: Giorgio A Tsoukalos and David Childress explore the mysterious chain of man-made islets in Micronesia's Nan Madol. Could local legends be true? (S12, ep 23).

The Relics of Roswell: In 1947, the US military collected debris of what they claimed was a crashed weather balloon outside Roswell, New Mexico. But was there more to it? (S12, ep 25).

Lancaster: Dan Jones visits Lancaster Castle to explore its grisly history of crime and punishment, including the infamous Lancashire Witches trials. (5 of 6).

The Holy Sepulchre of Jerusalem: Uncover the secrets of the Holy Sepulchre, the sacred Christian site built in the same spot as the death and resurrection of Jesus. (S3, ep 1).

Experts scrutinise the engineering behind the Egyptians' Sphinx and pyramids. Could this advanced civilisation have received extra-terrestrial help? (S1, ep 14).

Submerged: A Turkish drought reveals a long-lost Basilica and its secrets, while the hull of a ship in the North Sea answers decades-old questions. (S1, ep 4).

Destination Chile: Chile has the highest number of UFO sightings of anywhere on Earth. Now, incredible footage of a strange craft has people asking again about the reasons why. (S12, ep 26).

The Mystery of the Stone Giants: From Egypt to Easter Island, towering figures built by ancient man stand watch over Earth. But do they depict visitors from another world? (S12, ep 27).

Woolly Mammoths Last Stand: Travel to the most remote, uninhabitable parts of Earth to reveal great mysteries that have been frozen in time. (S4, ep 3).

Yak3: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 4).

Learn about Togo's traditional religious practices and take a tour of the incredible Danakil Desert in Ethiopia. Plus, visit a city in Georgia where every citizen has a gun. (S1, ep 3).

Destination Chile: Chile has the highest number of UFO sightings of anywhere on Earth. Now, incredible footage of a strange craft has people asking again about the reasons why. (S12, ep 26).

The Mystery of the Stone Giants: From Egypt to Easter Island, towering figures built by ancient man stand watch over Earth. But do they depict visitors from another world? (S12, ep 27).

From an Anglo-Saxon Burial ground to the caves of the Judean Desert and Siberia in the Ice Age, uncover the origins of the curses surrounding Sutton Hoo, Lyuba and more.

Arundel: Dan explores the history of the Earls of Arundel, how knights fought in the Hundred Years' War and how the Castle would have prepared for Queen Victoria's 1846 visit. (6 of 6).

Tikal: Discover Tikal, one of the largest and most powerful archaeological sites and urban centers of pre-Columbian Mayan civilisation. (S3, ep 3).

Yak3: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 4).

Ancient Civilisations: Nubian pyramids reveal the rise of female power in Ancient Kush, while satellite images uncover secrets of an ancient Puebloan site in New Mexico. (S1, ep 5).

Discover South Korea's seaweed farms, visit an Alaskan town where everyone lives under one roof and check out a flooded passage that leads to the French island of Noirmoutier. (S1, ep 8).

Alien Origins: The compelling series returns to examine more eerie reports of UFOs. Can it determine where in the universe such strange flying crafts could be coming from? (S3, ep 1).

Top Civilian Encounters: From mass sightings in the sky to reports of alien probes found in human bodies, explore the ten most disturbing extraterrestrial encounters ever. (S3, ep 19).

Escaping Devil's Island: Petty thief Rene Belbenoit is sentenced to time at France's notorious penal colony in French Guiana - but he is determined to escape or die trying. (S2, ep 5).

Dawn of the Animated Blockbuster: Facing soaring costs, mounting criticism and a tight deadline, Walt Disney creates the first full-length animated feature film. (S1, ep 2).

Woolly Mammoths Last Stand: Travel to the most remote, uninhabitable parts of Earth to reveal great mysteries that have been frozen in time. (S4, ep 3).

Beowulf: His epic battles with Grendel and his mother have made Beowulf the Viking world's most famous warrior. But could this mythological hero have been based on a real person? (S1, ep 1).

Destination Chile: Chile has the highest number of UFO sightings of anywhere on Earth. Now, incredible footage of a strange craft has people asking again about the reasons why. (S12, ep 26).

The Mystery of the Stone Giants: From Egypt to Easter Island, towering figures built by ancient man stand watch over Earth. But do they depict visitors from another world? (S12, ep 27).

Arundel: Dan explores the history of the Earls of Arundel, how knights fought in the Hundred Years' War and how the Castle would have prepared for Queen Victoria's 1846 visit. (6 of 6).

Notre Dame of Paris: One of the world's most popular cathedrals, Notre Dame suffered a devastating fire in 2019 - but how is it surviving today? (S3, ep 2).

Alien Origins: The compelling series returns to examine more eerie reports of UFOs. Can it determine where in the universe such strange flying crafts could be coming from? (S3, ep 1).

Top Civilian Encounters: From mass sightings in the sky to reports of alien probes found in human bodies, explore the ten most disturbing extraterrestrial encounters ever. (S3, ep 19).

Ancient Civilisations: Nubian pyramids reveal the rise of female power in Ancient Kush, while satellite images uncover secrets of an ancient Puebloan site in New Mexico. (S1, ep 5).

The World Before Time: New evidence reveals advanced civilisations might have existed on Earth thousands of years ago - is it possible that they lived with extraterrestrials? (S12, ep 28).

They Came From The Pleiades: In numerous ancient cultures, stories were told of ancestors from the Pleiades star cluster - could new scientific findings reveal the truth? (S12, ep 29).

Battlefield Beneath the Alps: In the Swiss Alps, a Roman dagger discovery reveals a 2,000-year-old battlefield where the Suanetes tribe fell to the Roman Empire. (S4, ep 4).

Hurricane: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 5).

Visit some of the world's most unusual houses, explore the Bangladeshi city with the largest number of cycle rickshaws and travel to the richest village in all of China. (S1, ep 4).

The World Before Time: New evidence reveals advanced civilisations might have existed on Earth thousands of years ago - is it possible that they lived with extraterrestrials? (S12, ep 28).

They Came From The Pleiades: In numerous ancient cultures, stories were told of ancestors from the Pleiades star cluster - could new scientific findings reveal the truth? (S12, ep 29).

From the time of the Knights Templar to pre-historic Spain, uncover the origins of the curses surrounding the Turin Shroud, the Cave of Altamira and more.

WW1 Special: To mark 100 years since the end of the Great War, Suggs and Stephen excavate the site of a huge World War One transit camp at Morn Hill, outside Winchester.

Chichen Itza: Considered one of the New Seven Wonders of the World, the Mayan City of Chichen Itza was the capital of a powerful civilisation. (S3, ep 4).

Hurricane: Explore classic and underrated aircraft, from WWII fighters to the Screaming Eagles F4, showcasing aviation's evolving history. (S3, ep 5).

Unreachable Places: Discover strange markings in the remote region of Northern Finland and reveal secrets found deep in the Antarctic. (S1, ep 6).

Uncover the secrets behind the San Bernardo mummies, visit the fascinating Skatopia in Ohio and take a closer look at the living conditions in Siberia. (S1, ep 9).

Astronaut Encounters: To this day, NASA denies all UFO accounts and has taken measures to prevent its astronauts from telling their stories. But what are they hiding? (S3, ep 3).

Atmospheric Anomalies: Some experts believe many atmospheric light shows are actually caused by extraterrestrials. If so, do they pose an imminent threat to humanity? (S3, ep 4).

The Lost Continent (Atlantis): Atlantis, the legendary continent that sank. As the Nazis rose to power, Himmler and the SS were convinced Atlantis existed. Season premiere. (S1, ep 1).

The Model and the Maniac: The prime suspect of a gruesome triple homicide, wax sculptor Robert Irwin sold his story to finance his defence and escape the death penalty. (S1, ep 1).

Battlefield Beneath the Alps: In the Swiss Alps, a Roman dagger discovery reveals a 2,000-year-old battlefield where the Suanetes tribe fell to the Roman Empire. (S4, ep 4).