Two survivalists are stranded at sea and have to survive for 21 days with no food, water or clothes. They must put their skills to the test to overcome deadly sharks and heatstroke that threaten their survival.

A surfer from Hawaii and an ex-military take on the Texas countryside, surrounded by armadillo, bighorn sheep and vicious wild boar; as they battle starvation and face a potentially fatal flood, their skills get fully put to the test.

Two complete strangers - man and woman- are left naked and stranded on a desert island.

A mom and an adventure addict drop into the cloud forest of Ecuador; unbearably wet conditions, violent lightning, cabin fever, trench foot and finger-slicing machetes threaten to keep the pair from completing their 21-day challenge.

An Army vet and a newly married man grapple with gender norms as they take on the mountains of Croatia; extreme hunger and frigid temperatures force this unlikely pair to bond together, but a vicious storm threatens to rip them apart.