Arctic Hell

The men pick their route: some take the higher land, some follow the river. Expert climber Willi Prittie leads Brent Sass and Tyler Johnson into the mountains. The bearing they're traveling reaches elevations over 4,000 feet. Veteran mountain man Marty Raney is leading his son Matt and survival expert Austin Manelick through the river valley. Brothers Dallas and Tyrell Seavey navigate along the ridgeline, crossing land with little cover. These born racers are resolute to be the first to arrive.

River of No Return

The men are divided into two groups, building competing rafts. Mountain man Marty Raney is taking charge, building a colossal raft weighing nearly 2 tons which he hopes will be sturdy enough in the rapids. After spending five hours on construction, the five-man crew get on their way, but hunger starts to take its toll. Dallas Seavey, his brother Tyrell and survival expert Austin Manelick are meticulously engineering a smaller raft that's speedy and maneuverable to tackle the turbulent Yukon.

Into the Void

Helicopters leave the eight explorers on a snow-capped summit. The men split into three groups and approach a 300-foot cliff, descend a ravine and traverse eight miles of the Triumvirate Glacier. Marty Raney, his son Matt and Brent Sass take a low route and are the first to cross. Willi Prittie and the Seavey brothers cross far from the icebergs, across 33-degree water. Austin and Tyler bypass the glacier, traveling along the ridgeline. They arrive last and Austin's showing signs of hypothermia.

Sink or Swim

The eight explorers are on the fourth leg of their expedition and are struggling to stay afloat on the Talachulitna River. With currents rushing at dangerous speeds, it's no easy feat to navigate the frigid waters. Expert climber Willi Prittie teams up with Iditarod champion Dallas Seavey and his brother Tyrell to find a much-needed food source. Meanwhile, mountain man Marty Raney and his son Matt enter the river further downstream hoping to minimize their time on the water.

Belly of the Beast

The explorers brave the dangers of Alaska's "Bear Highway" only to find themselves stranded and fighting to survive Mother Nature's fury on the shores of Katmai Bay.

Desolation Island

Facing the brink of collapse, the eight starving explorers set out with one mission: harvest as much food as possible from the barren landscape of Nunivak Island.

Desperate Measures

In this leg of the expedition, the eight survivalists paddle 40 miles through a minefield of icebergs and glaciers in Prince William Sound.

Ice Cold Gamble

On day 32 of the expedition, the explorers traverse the Nizina River Valley, a vast expanse of land known for its lush wildlife, hungry grizzlies and homesteaders living hundreds of miles from civilization.

Beasts of Prey

The explorers travel to Admiralty Island, home to the highest density of brown bears in North America, and it's not long before they receive a "grizzly" welcome.

Vertical Hell

On the last leg of the 3,000-mile journey across Alaska, the explorers battle a brutal winter snowstorm as they climb a 5,000 foot mountain in the Juneau ice field.

Arctic Battleground

Savage Beasts

Over the Falls

Climb From Hell

River of Fury

Hell Hole

Vice Grip

Guts & Glory

River of Doom

Bear Kingdom

Deep Dark Woods

The Last Battle

Fight to the Finish

Episode 14

Episode 15

Back for Blood

Deadly Descent

Crash Course

Deadly Tide

Devil's Due

Rogue Warrior

Live Before You Die

Savage Waters

Kodiak Killers

Covert Ops

Long Way Down

Knockout Punch

Final Gauntlet