A survivalist postpones her wedding to try 21 days in the Colombian jungle.

When a third survivalist crashes the challenge, tension and jealousy are just as threatening as the piranha and jaguars of the Ecuadorian rainforest. Claims that there's more going on than just survival puts everyone's challenge at risk.

Two foreigners try to become the first survivalists to endure 21 days on U.S soil. But rattlesnakes, unfamiliar terrain and plummeting temperatures threaten to send them back across the pond. Lilly from Austria and Sam from the UK team up to do battle with the New Mexico wilderness.

After surviving a near-fatal fall, an equestrian stunt rider attempts to endure 21 days in Colombia.

In an unprecedented Naked and Afraid challenge, identical twin sisters Amber and Serena, as well as brothers Warren and Thomas, are dropped in the African savannah. They take on rhinos, hyenas and a territorial leopard stalking their camp.

Dropped onto a frozen Alaskan Glacier, All-Star survivalists Laura Zerra and Steven Hall scramble to stave off frostbite and hypothermia. And 7,000 miles south, two new survivalists take on a sun-scorched Brazil island, with anaconda and deadly stingray.

Legend survivalists Max and Rylie are dropped in the South African bush with two novice fans to try and survive 21 days with spitting cobras, aggressive warthogs, rhinos and leopards.

Language barriers stand between two survivalists in the South African bush.

A hunter and a farmer pool their knowledge as they attempt to survive 21 days in South Africa. But when the wildlife proves too stealthy to hunt, the survivalists take a life-threatening risk for food.

A self-proclaimed 'king of the forest' and an endurance athlete tackle the backwoods of Alabama. They secure shelter and a fire early on, but when hunger kicks in, one of them does something that's never been seen in show history.

In the snake-filled Mississippi swamps, Gabrielle, a former fan survivalist takes on the full 21-day challenge. Gabrielle and Brian are faced with deadly snakes, unrelenting mosquitos, nocturnal predators and a relentless week-long thunderstorm.

On the edge of the Bermuda Triangle, an Army veteran dive master and a Cajun boat captain take on relentless thunderstorms and battle dehydration as they try navigate more than 20 miles of open ocean in the ultimate test of sink or swim.

A survival-savvy yoga teacher and a custom knife maker tackle the brutal jungle of Colombia. Their primitive survival skills are impressive, but the deadly spiders and tics test both their courage and resilience, threatening to take them down.

In the relentless Colombian jungle, a mom and National Guard vet teams with a firefighter. Violent storms and hypothermic conditions force them to huddle in bat-infested caves. A special bond develops between a survivalist and a wild monkey.

Crippled by injuries and toxic frogs, an adrenaline junkie and a self-proclaimed renaissance redneck must dig deep to try to endure 21 days in Colombia.

Jaclyn McCaffrey and Adam Young survive in Nicaragua for battling with dehydration and freezing temperatures.

An Army mom and a U.S. marine battle alligators, snakes and mosquitoes in the Florida Everglades.

A category five Hurricane blasts through the camp of Amal, an Iraqi war refugee now living in Iowa and her partner, Duke. In addition to the hurricane, the pair also endure venomous spiders, insects, and nocturnal predators in the swamps of Florida.

A survivor of rattlesnake, shark and bear attacks teams with Brooke, wife of "Naked and Afraid" veteran Matt Wright, in a vicious African feeding ground.

In this all-female tribe’s challenge, two veteran survivalists return to mentor two newcomers on the perils of San José Del Guaviare, Colombia, for 21 days. But, scarce food resources and torrential tropical storms take a quick toll.

Instant attraction gives way to unforgiving conditions on a Nicaraguan island teeming with bull sharks and big cats. As the struggle to survive hits a low point a brutal flood threatens to wipe out the camp and all chances of survival.

Surrounded by aggressive and territorial black bears day and night, two survivalists must compete against the apex predators for resources in the Smoky Mountains of Tennessee.

In the frozen American Rockies, snow storms and freezing temperatures force the survivalists to make risky choices with their fire and food sources. An out of control blaze and toxic mushrooms put their challenge and safety at risk.

A workaholic mom and a loner are challenged to survive three weeks in Thailand.

Two fans are selected for a two-week long challenge in Nicaragua.