National Geographic Channel HDTV (NGCHD)

At Colombia's biggest airport, officers uncover cocaine-smuggling methods. (Repeat).

At Colombia's biggest airport, cocaine is found in laptops and people's bodies. (Repeat).

Exploring the profound impact of artificial intelligence on peoples daily lives. (New).

At Colombia's biggest airport, officers make cocaine busts in bags and mail shipments. (Repeat).

At Colombia's biggest airport, officers make cocaine busts in bags and mail shipments. (Repeat).

At Colombia's biggest airport, officers make cocaine busts and uncover fake documents in the series premiere. (Repeat).

At Colombia's biggest airport, officers make cocaine busts and uncover fake documents in the series premiere. (Repeat).

An American woman's attempt to adopt a child from Egypt goes terribly wrong. She's charged with fraud after trying to acquire a birth certificate and a passport for her adopted son. (Repeat).

An American woman's attempt to adopt a child from Egypt goes terribly wrong. She's charged with fraud after trying to acquire a birth certificate and a passport for her adopted son. (Repeat).

In 1976, at the height of the Cold War, an American is caught smuggling heroin from Kuala Lumpur to Russia. He details his incarceration in a Soviet prison camp and his eventual escape during a power outage. (Repeat).

In 1976, at the height of the Cold War, an American is caught smuggling heroin from Kuala Lumpur to Russia. He details his incarceration in a Soviet prison camp and his eventual escape during a power outage. (Repeat).

A young man travels to Pakistan and sets off on a once-in-a-lifetime journey with his estranged dad along the historic Silk Road, unaware that his dad is a veteran cannabis smuggler with plans to bring 20 kilos of the drug into China. (Repeat).

A young man travels to Pakistan and sets off on a once-in-a-lifetime journey with his estranged dad along the historic Silk Road, unaware that his dad is a veteran cannabis smuggler with plans to bring 20 kilos of the drug into China. (Repeat).

The lure of easy money leads an out-of-work father to smuggle cocaine from Nicaragua into the U.S. After several successful trips, he gets caught by customs agents and is sent to a hostile Nicaraguan prison. (Repeat).

The lure of easy money leads an out-of-work father to smuggle cocaine from Nicaragua into the U.S. After several successful trips, he gets caught by customs agents and is sent to a hostile Nicaraguan prison. (Repeat).

An Orthodox Jew from London becomes a key player in an international cocaine-smuggling ring based in São Paulo, Brazil. After exporting hundreds of kilos of the drug, his luck runs out and he lands in the notorious Carandiru Penitentiary. (Repeat).

An Orthodox Jew from London becomes a key player in an international cocaine-smuggling ring based in São Paulo, Brazil. After exporting hundreds of kilos of the drug, his luck runs out and he lands in the notorious Carandiru Penitentiary. (Repeat).

Life in a notorious Bangkok prison is detailed by a woman who received a life sentence for attempting to smuggle heroin out of Thailand. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

A look at how Hitler's vast network of railways became the lifeblood of the Nazi empire, spreading Hitler's ambition and control across Europe and beyond. (Repeat).

A look at how Hitler and Holocaust leader Heinrich Himmler used a vast rail network to transport Jews to their death. (Repeat).

The story of Hitler's Italian Fortress. (Repeat).

Season 4 takes off with a study of the Luftwaffe, Hitler's air force. (Repeat).

When defeat was inevitable, the Propaganda Machine was used by the Nazis to motivate civilians to fight. (Repeat).

The Nazis' occupation and fortification of Norway is spotlighted. (Repeat).

In Port Protection, tools aren't always used for what they're intended. (Repeat).

Curly helps in fighting some deadly trees on his neighbor's property. (Repeat).

As Mother Nature tries to take back the land, residents work to ensure the community's safety and success. (Repeat).

(Repeat).

In this enhanced episode, Oliver brings in a haul with new fishing pots. (Repeat).

Milestone achievements are only possible with steep challenges in Port Protection. Carl and Matt pull a three-thousand-gallon barrel up a cliff. (Repeat).

(Repeat).

(Repeat).

Milestone achievements are only possible with steep challenges in Port Protection. Carl and Matt pull a three-thousand-gallon barrel up a cliff. (Repeat).

(Repeat).

(Repeat).

A look at how Hitler's vast network of railways became the lifeblood of the Nazi empire, spreading Hitler's ambition and control across Europe and beyond. (Repeat).

A look at how Hitler and Holocaust leader Heinrich Himmler used a vast rail network to transport Jews to their death. (Repeat).

The story of Hitler's Italian Fortress. (Repeat).

Season 4 takes off with a study of the Luftwaffe, Hitler's air force. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

Paid Programming. (Repeat).

In the '70s, John Gotti fights to become boss; in the '80s Whitey Bulger terrorizes Boston. (Repeat).

One drug lord created Mexico's first narco army, unleashing a cartel feared by all. (Repeat).

Meth kingpin Nazario Moreno turns a drug cartel into Mexico's first narco cult. (Repeat).

Pablo Escobar is spotlighted. (Repeat).

Two Chicago women and their drug-dealing husbands helped bring down El Chapo. (Repeat).

Interviews reveal how criminals pioneered the cocaine business in the '70s and early '80s. (Repeat).

AMO hunts for a boatload of coke. CBP finds a hidden body in a trunk. (Repeat).

HSI conducts an undercover drug sting; CBP discovers cocaine in the Rio Grande Valley. (Repeat).

CBP's K9 detects hidden cash. HSI intercepts a two-million-dollar drug trade. (Repeat).

Meth and fentanyl are discovered during an HSI stakeout, while CBP intercepts a shipment of cash and cocaine. (Repeat).

JFK's CBP and HSI in San Diego face a crisis on fentanyl. (Repeat).