Nine show veterans are dropped in groups of three deep inside Ecuador's water-soaked rain forest and get a harsh introduction to the dangers of the swampy landscape. The all-female team struggles for days to get fire in the damp environment, and the all-male team is shattered by a devastating injury on Day One.
The remaining survivalists enter the second week of the challenge, and one team stalks a pack of wild pigs deep into the jungle. Then, one competitor falls victim to extreme sleep deprivation, and a lack of food and conflicting priorities creates serious tension within the all-female group.
The all-female team's successful night-fishing trip boosts their morale, but another freak accident leaves them reeling. Lack of food and sleep at another camp causes one competitor to continue her downward spiral as her partner tries desperately to convince her they should search for other survivalists.
As they approach the halfway point of their brutal, 40-day challenge, the remaining survivalists merge into a single team. However, they're dealt a devastating setback when deadly bacteria threaten to take out their leader.
The remaining survivalists endure another shocking development as their world collides with two other survivalists nearing the end of their challenge. Desperate for more able bodies to help get them through the final half of their 40 days, the group invites the duo to stay.
In a surprise move to establish himself as the provider of the group, one survivalist leads the men to his old camp for a two-day pig hunt, leaving the women to fend for themselves. Then, the newest member wrestles with his darkening thoughts deep in the unrelenting jungle.
Four weeks into the brutal 40-day Amazon challenge, a violent two-day storm descends on the jungle. Before it’s over, one more survivalist will be gone, leaving another hanging by a tenuous thread.
After Russell’s shocking decision to quit the Amazon challenge, the remaining survivalists struggle to regroup in time for a brutal two-day 15-mile water extraction journey. Electric eels, anaconda and caiman all pose threats in this jam-packed finale.