TV Guide National Geographic Channel Tuesday

Fails include a broken Baltimore bridge, a Manhattan crane fire and a poonami in China.

Earthquake-proof buildings fall down; a battery factory blows up, and a bridge collapses.

The U.S. government's secret Pentagon Program on UFO's is exposed.

Project Blue Book is launched to study the country's growing UFO problem.

United States nuclear missiles malfunction after a close encounter with Unidentified Flying Objects.

More military and commercial pilots are reporting seeing Unidentified Aerial Phenomena, or UAPs, in flight.

As the Alaskan residents make a life for themselves out in the rugged wilderness, they rely on their ingenuity as they construct what they need to survive.

On the first leg of his trek into the Great Rift Valley, Hazen Audel battles the arid Chalbi desert on a mission to find a tribal camel train.

Hazen Audel descends sheer slopes into the Great Rift Valley, trenches that runs from Lebanon in Asia to Mozambique in Southeast Africa, in search of elephants.

Hazen Audel battles Lake Baringo's wild waters of the Kenyan Rift Valley lakes, on an epic wildlife mission.

Hazen Audel hits Hell's Gate gorge in Kenya, in search of rare black rhino.

Hazen Audel tackles the Indian Ocean in a battle to reach a network of coastal coral caves, home to the largest bat colony in Africa.

In an epic finale, Hazen Audel takes on the Serengeti wilderness as he battles to reach his ultimate goal, the great wildebeest migration.

The villagers of Port Protection are back to paving with good intentions.

Curly shoots a bear; Troy and Sarah struggle with a new water system.

Residents tackle tasks at the height of summer's season of productivity.

All around Port Protection, neighbors lend each other helping hands.

In Port Protection, their canine community takes center stage.

Curly takes advantage of a break between storms to hunt for deer.

Port Protection residents must harvest from land and sea for survival.

As the Alaskans continue in their personal missions to eke out a life in the remote wilderness, they each lead risk-filled lives every day.

Curly takes advantage of a break between storms to hunt for deer.

Racing to the rescue, rookie Terje's in trouble when he crashes Thord's tow-truck; Thord risks it all to rescue a garbage truck on a sheep's road.

Hazen Audel battles Lake Baringo's wild waters of the Kenyan Rift Valley lakes, on an epic wildlife mission.

Hazen Audel hits Hell's Gate gorge in Kenya, in search of rare black rhino.

Hazen Audel tackles the Indian Ocean in a battle to reach a network of coastal coral caves, home to the largest bat colony in Africa.

In an epic finale, Hazen Audel takes on the Serengeti wilderness as he battles to reach his ultimate goal, the great wildebeest migration.