Historians, engineers, ​and experts take a look at the underground structures, systems, and phenomena that exist beneath our feet.

The black market can be brutal, exploitative, corrupt. Nothing is off-limits; everything is for sale. And what you buy may not be what it seems. But it’s an industry estimated to be worth hundreds of billions of dollars in the U.S. alone. Join the suppliers, sellers, customers, and the law enforcement officials trying to keep it in check as they share their experience of a hidden world that touches us all.

Filmmaker Joe Berlinger’s real-time, eight-part investigation into a string of mysterious sex and drug-fueled disappearances and deaths in the heart of America’s rust belt.

Ex-CIA operatives Doug Laux and Ben Smith search for the rumored millions hidden by Pablo Escobar in Colombia and Central America.

Each episode of this true-crime series begins with the grisly discovery of a body and the onset of an intense investigation. When police think they’ve solved the case, shocking twists sends each investigation into the depths of evil.

David Attenborough presents a documentary series exploring how animals meet the challenges of surviving in the most iconic habitats on earth.

From germs and emotions to social media and more, it’s the science of your world explained in a way that’s refreshingly relatable.

Documentaryseriesexaminingtheimpactofimmigrationuponasinglecommunity,PageHallinSheffield.Eacheditionfocusesonadifferentcommunityinthearea.

Tony Robinson dons his hiking boots to explore the 200-mile coast-to-coast route made famous by travel writer Alfred Wainwright. In the six-part series, Tony will be trekking across the north of England from St Bee’s Beach in Cumbria to Robin Hood’s Bay on the Yorkshire coast.

Viewers go deep into an Alaskan winter to meet six tough and resilient residents as they try to stay one step ahead of storms and man-eating beasts to make it through to spring. The closest neighbor to Sue Aikens is more than 300 miles away. Eric Salitan subsists solely on what he hunts and forages. Chip and Agnes Hailstone catch fish for currency in bartering for supplies, and Andy and Kate Bassich use their pack of sled dogs for transportation.

“The first sports-based reality series” in television history presents viewers with an inside look at NFL training camps. From the top coaches to the rookies trying to make the team, Hard Knocks will showcase what it takes to be in the NFL.

In the frontier town of Nome, Alaska, there’s a gold rush on. But you’ve never seen gold mining like this before — here, the precious metal isn’t found in the ground. It’s sitting in the most unlikely of places: the bottom of the frigid, unpredictable Bering Sea. And there are a handful of people willing to risk it all to bring it to the surface.