Paul heads over to the local reservoir, and notices a body floating in the lake. The marks Paul made on her back are shown to be developing into gruesome wounds like Karen's. Now completely alone, Marcy has a bath and weeps. Marcy urges him to stay, but Paul seems uncomfortable around her after sleeping with her and insists that he 'has to get out of' the cabin. A little later, Paul tells Marcy that he's going to bring back Jeff so that they can all walk back to civilization. While washing her face, Marcy discovers, with worry, some red marks on her back where Paul grabbed her in the heat of their sexual encounter.

He goes into the bathroom and attempts to disinfect his penis by pouring Listerine over it. After they finish having sex, Paul worries about whether Marcy has the disease or not. Marcy brushes him off without heed by saying 'Don't worry, I'm healthy!' and continues riding him. Paul expresses concern that they aren't using a condom. He tries to reassure her, but she reiterates that they are all doomed to get sick, to the point where 'all you want to do is grab the person next to you and to have sex with because you know you're gonna be dead soon, anyway.' She seduces Paul and they begin having wild sex. Now alone in the cabin, Paul finds Marcy sitting despondently on her bed. Bert speeds off and the father grabs two of his redneck friends (Richard Boone and Tim Parati) who arm themselves with rifles to go after Bert to kill him. His father (Hal Courtney) comes outside and, rather than helping Bert, tries to kill him. The young retarded redneck boy on the bench then runs over and bites Bert again, thereby infecting himself. Meanwhile, Bert drives to the convenience store that the group visited earlier pleading for a doctor. Marcy yells at him as he flees, upset that he has abandoned her. When Paul and Marcy insist on helping Karen, Jeff runs off into the forest with the remaining beer (the only reliable drinking source). Bert also realizes that he himself is infected with the virus. The next day, they discover Karen's condition is deteriorating fast. Fearing that they will soon also become infected with whatever is ailing Karen as well as the man the night before, the others begin to argue with one another over what they should do about their situation. Karen is then quarantined in the tool shed outside. Paul later discovers rotten boils on her thighs. During this time, Karen drinks a glass of water from the lake contaminated by the infected man and begins to feel ill. They soon discover that the woman was related to the hermit they killed so they leave quickly. Jeff and Bert walk off down the lake shore when they come to a woman's house to ask for a ride into town. In the morning, a young deputy, Winston Olsen (Giuseppe Andrews), shows up at the cabin and promises Paul he'll call a tow truck. After the man exits the car, Paul sets-light to the infected man and he runs aflame back into the woods where he dies in the lake. He tries to drive away in their car, but vomits blood all over the windscreen and the seats of the car. Desperate for help, the hermit comes after the group. Later on that night, they hear a knocking at the door and discover it's the diseased man that Bert shot before. However, once it starts raining, he leaves to take care of his camping equipment and the group retreats into the house. Though he acts a little eccentric, they allow him to join in when he offers them marijuana. They soon encounter a local college kid named Grim (Eli Roth) who approaches them with his dog, Dr. That evening, the five kids build a bonfire and share ghost stories with each other. Scared, Bert shoots at him again in order to repel him and runs back to the cabin.

By this time, the man's face has become badly rotted. He accidentally shoots the man who discovered the rotting dog in the beginning of the film while hunting whom he mistook for a squirrel. Paul and Karen go for a swim in the lake while Bert goes hunting for squirrels in the woods. When they arrive at the cabin, Jeff and Marcy immediately retire to their bedroom and have sex. The locals standing nearby look at the outsiders in their town with suspicion and scorn. Along the way, they stop at a local convenience store for food where a young boy (Matthew Helms) outside the store bites Paul on the hand. Meanwhile, five college friends, Jeff (Joey Kern), Marcy (Cerina Vincent), Paul (Rider Strong), Karen (Jordan Ladd), and Bert (James DeBello) are driving in a van through rural Alabama on their way to the woods for they have rented a cabin in the woods. After poking it a few times, he pulls the dog up and notices that the dog's flesh is rotted, spurting blood on him in the process. A man (Arie Verveen) is walking in the woods and comes upon a dog that he believes to be sleeping.

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