Three adventurous young American travelers, Alex (Josh Duhamel), his sister Bea (Olivia Wilde), and their friend Amy (Beau Garrett), are exploring Brazil while backpacking. Opting for a bus journey instead of a direct flight to the sun-kissed beaches of the North-East, their plans take a drastic turn when a bus accident leaves all passengers stranded. They team up with two English men, Finn (Desmond Askew) and Liam (Max Brown), along with an Australian woman named Pru (Melissa George), who speaks Portuguese fluently.
Seeking refuge from their misfortunes, the group sets off to a nearby beach, where they discover a lively cabana bar teeming with fellow tourists and fun. A day filled with swimming and merriment quickly takes a dark turn when they are served spiked drinks, resulting in their unconsciousness. The next morning, they awaken to the stark reality of having been robbed, left without their luggage, money, or important documents on a desolate beach.
Desperate for help, they stumble into a nearby village and realize the locals are donning some of their belongings. There, Kiko (Agles Steib), a local who speaks English, offers to escort them to a secluded cabin in the woods while they await assistance. After a strenuous journey through the wilderness, Kiko reveals a hidden sanctuary: a cave behind a waterfall. Unfortunately, a reckless dive results in Kiko sustaining a severe head injury, leaving him unconscious and bleeding.
Upon reaching the cabin, the group discovers a stash of clothes, food, and prescription medications under a variety of names, alongside a drawer brimming with other people's passports. They manage to treat Kiko's wound and settle in for the night, unprepared for the chaos that awaits them. In the dead of night, a helicopter arrives, bringing Zamora (Miguel Lunardi), a physician, and his armed associates. A woman forewarns them to escape, but confusion reigns as they mistakenly confront the intruders, only to be overpowered.
> Zamora chillingly expresses, "It's time to give back," as he begins a brutal procedure in which he removes organs from Amy, sedated and unaware of her impending doom. This harrowing act reveals the sinister reality of organ trafficking targeting foreigners for the benefit of the impoverished locals.
Meanwhile, Alex and the remaining group members manage to break free from their confines and, with Kiko's help, face off against one of Zamora's henchmen. As Bea and Pru flee into the dense jungle, Alex, Liam, and Kiko plan a daring raid on the cabin to rescue Finn, who's been left partially incapacitated from the sedation. In the chaos that ensues, Finn tragically loses his life when shot. As they regroup, Alex realizes their urgency in escaping, while Liam heroically resolves to confront their enemies, only to meet a similar fate.
Separated in the jungle, Alex and Kiko eventually find Bea the following morning. Together, they navigate to a now-flooded cave, evading an associate of Zamora who hunts them with a bow and arrows. After a perilous swim, they reunite with Pru, only to come face-to-face with Zamora, who fatally shoots Kiko and injures Alex.
In a desperate bid for survival, the trio navigates through tight air pockets while being pursued. Bea encounters the archer in a crucial moment and, using ingenuity, overpowers him by stabbing him with an arrow. As they barely escape the cave, another confrontation with Zamora leads to a chaotic battle. Alex, fueled by rage, attacks Zamora, just as one of his henchmen hesitates, ultimately turning the gun on Zamora instead.
Afterwards, the surviving group is miraculously rescued by empathetic local villagers. The film concludes with Alex, Bea, and Pru silently standing in line to board a plane, reflecting the deep scars of their traumatic experience, as Alex advises a pair of arguing tourists to take the plane instead. The final shot captures the three, united yet haunted, as they board the flight that will carry them away from their nightmare into an uncertain future.
