A serial killer, Butch, escapes prison and murders an officer, before posing as his victim so he can disappear in the remote Grizzly Park. To keep his cover, Butch picks up eight troubled young teenagers who are inducted into a rehabilitation program, in Grizzly Park, to serve a week of community service for their respective misdemeanors: Michael 'Scab' White, Lola, Bebe, Ty, Candy, Ryan, KiKi and Trickster. Arriving at Grizzly Park, the group meet Ranger Bob and Ranger Mike. Ranger Bob sets off with the group into the park, while Ranger Mike stays with Butch, who quickly stabs him to death before entering the park himself. However Butch is soon attacked and killed by a large Grizzly bear.
Through their hike, the teens are given an opportunity to seek redemption; however this fails, as the group ignore Ranger Bob and instead spend the majority of the hike lusting after each other. Ty and Kiki sneak off from the group, but Ty becomes stuck in a wolf trap. His blood attracts a wolf which attacks and murders KiKi, before the grizzly bear murders Ty. The rest of the group reach the main camping site where they spend the night.
In the morning, when Ty and KiKi have not arrived, Ranger Bob goes out to look for them, leaving the group at the camp where they continue to lust for each other. At night, after hours of searching, Ranger Bob discovers the gory remains of Ty and KiKi, and begins to rush back to the camp, where the group are having a campfire. Scab leaves the group and inhales gas, while Trickster dresses up in a bear costume to scare the others. While Scab is on a drug trip, the bear attacks and kills him, his death going unnoticed due to Trickster's prank. However, soon after the bear attacks the group, decapitating Trickster and mauling Lola in half.
Ryan, Candy and Bebe hide in a shed, but the bear attacks. Thinking the bear has left, Ryan opens a hatch; however the bear drags him out and begins to maul him to death. Candy and Bebe attempt to pull him back in, but his arms are torn from his body and he dies. Sometime later, the bear attacks the shed once more. Bebe escapes while closing the door at Candy's face, which force her to stay behind and be killed by the bear.
The following morning, Ranger Bob returns to find an upset Bebe. As Bebe prepares to leave the camp, Ranger Bob overhears her making a call to her friend telling her she had manipulated Ranger Bob and planned to murder him. As Bebe leaves the cabin, she encounters the bear and it brutally kills her. Afterwards, a news reporter is seen explaining the murders to be at the hands of Butch, who supposedly dressed up as a bear and killed the victims before escaping. It is revealed that Ranger Bob, in fact, trained the bear to kill the members of the group who had not learned from their previous mistakes.