Nat Geo HD Schedule, Today (United Kingdom)

Apes: Mariana heads to the Congo to investigate the illegal trade of wild apes that have them on the brink of extinction, following the supply chain from poachers to buyers. 16+. (4 of 10)

Yde Girl: Murder on the Edge of Town: When human remains are found in the Netherlands, locals blame the Devil - but the truth is more chilling than imagined. 12+. (S1, ep 6)

Oil City, Pennsylvania Bank: The team salvage elegant furnishings and historic gems, as they search a former bank that once held the fortunes of rich oil barons. (S1, ep 8). All Ages.

Blondies & Cheddar Cheese: Find out what it takes to make a 5,000-pound monster cheese wheel, before taking a bite out of these irresistible blondies. U. (S2, ep 20)

Curds & Cow Pie Candles: Discover how to make three million deep-fried cheese curds in a day, how to turn a mountain of pecans into cow patties and why popping candy pops. U. (S2, ep 21)

Pirate's Deadly Pistol: An 18th-century flintlock is up for auction. The four-barrel gun was extremely expensive to produce, making it coveted booty for pirates. All ages.

The Secret Flame: A World War II searchlight seeks out the team in Colorado, where Sean also finds a simple Italian flintlock that hides a deep and valuable secret. All ages.

Karma Chameleon: Dr W examines Toothless, a chameleon with a swollen eye. Dr K meets Snowball the pine snake, who has stopped laying her eggs. RATING: NU12 (S1, ep 8)

Who Let The Hogs Out: Biggie is a rescued potbellied pig whose eyes are irritated. Dr K gives him one of her special piggy eye lifts. RATING: NU12 (S1, ep 9)

Teleshopping.

Pasta the Olives: Discover how succulent stuffed olives get from branch to jar, and how 12,000 plates of tasty tortellini are made per day. (S1, ep 21) RATING: AA

In a Jam: A look at how traditional methods still factor into modern-day croissant production and why shredding is key to making delicious rhubarb-strawberry jam. (S1, ep 22) RATING: AA

Lost Treasures Of Egypt: Using the latest technology and research, dive beneath the Nile and uncover a missing ancient wonder and once fabled city of the early Egyptian world. U. (S4, ep 4)

Relentless Pursuit: Werner Henke and his crew faced one of their toughest tests of the war when they ran into one of the Hunter Killer Group's anti-submarine warships. (S2, ep 3). All Ages.

Defying Rommel: The story of HMS Upholder and HMS Unbeaten - two British submarines who unknowingly took aim at each other while hunting Italian supply ships. (S2, ep 4). All ages.

Breakout From Normandy: The Allies have captured the beaches of Northern France and must now head into enemy territory. Join them on their bitter two-month march to liberate Paris. U.

Operation Market Garden: It's 1944, and the Allies have launched a daring attack on the Nazi-occupied Netherlands in a bid to bring World War II to an end. U.

Did drugs affect Hitler's actions and behaviour? Find out in this compelling documentary examining the medications the dictator was taking, how much he took and how often.

Thanks to the discovery of an unknown film, see the reasons behind the flaming crash of the Zeppelin Hindenburg in black and white. RATING: AA

Parting the Red Sea: Did Moses really part the Red Sea? Albert Lin heads to Egypt where he uses cutting-edge technology to hunt for long-buried clues about the famous Bible story. All ages.

Sodom and Gomorrah: Could the Bible's greatest disaster story have been inspired by real events? Albert Lin heads to the Holy Land to find out. All ages.

Terror Over the Pacific: When a massive explosion tears a hole in a 747 over Hawaii, the search for answers ultimately leads to a deadly short circuit. U. (2 of 10)

Meltdown Over Kathmandu: Landing at one of the world's most challenging airports, a passenger plane comes in like a fighter jet, skids off the runway and bursts into flames. RATING: NU7

Massacre Over The Mediterranean: In 1980, Itavia Flight 870 exploded over the sea. After 30 years of investigations, experts reveal the truth behind the mysterious disaster. RATING: AA

Malaysian 370: What Happened?: In this special episode, examine one of the greatest aviation mysteries of all time - the disappearance of Malaysia Airlines Flight 370. U.

Experts investigate the fate of Port Royal. Known as 'the wickedest city on Earth', it was a famous hangout for pirates until an earthquake and tsunami sucked it into the ocean. All ages.

The Real Black Hawk Down: The true story of the 1993 Battle of Mogadishu, where Somali militia fighters shot down two American helicopters and killed 18 US soldiers. (S1, ep 2). All Ages.