Lindsey Leitelt and Luke McLaughlin challenged in a dense harsh land in Namibia.

Dani Julien and Justin Bullard stranded with starvation and tiny predators in the Bahamas' Andros islands.

Carrie Booze and Tom Touw survive with crocodiles and extreme heat in Cambodia.

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

Survival coach Tom McElroy and pediatrician Lisa Coray fight with storms and dehydration in Argentina's Yungas forest.

Corinne Kohlen and Chris Fischer are stranded on a deserted beach in Dominica. Corinne tapped out on day 13, and Chris left alone for full 21 days.

Hakim Isler and Phaedra Brothers tackle the high altitude and extreme cold of the Himalayan foothills in northern India. Phaedra battles food poisoning from before her arrival and suffers through bladder and kidney infections.

Joshua Bell and Amanda Leigh face the hot and swampy jungles of southern Nicaragua while armed with only a machete and a roll of duct tape. Joshua leaves early on day 5 for dehydration and Amanda survives all alone for the rest of the 21 days.

Ashley Burns and Michael Jefferson attempt to survive dazzling heat in Botswana. Ashley medically evacuated on day 3 after suffering dizziness, while Michael tapped out on day 12 after hurting his kidney.