Description
Emma and John Collingwood, and their daughter, competitive swimmer Mari, head out on vacation to their lake house. Shortly thereafter, Mari borrows the family car and drives into town to spend some time with her friend Paige. While Paige works the cash register at a local store, she and Mari meet Justin, a teenager passing through town who invites them both back to his roadside motel room to smoke marijuana. While the three are hanging out in the motel room, Justin's family members return: his father, Krug, his uncle, Francis, and Krug's girlfriend, Sadie.
Krug becomes angry at Justin for bringing unknown people to their motel room, and shows him a local newspaper that has Krug and Sadie's pictures on the front page, and which explains how Sadie and Francis broke Krug out of police custody and killed the two officers that were transporting him. Believing it would be too risky to let Paige and Mari go, the gang kidnaps them and uses their car to leave town. While Krug searches for the highway, Mari convinces him to take a road that leads to her parents' lake house; Mari then attempts to jump out of the vehicle, but the ensuing fight among the passengers causes Krug to crash into a tree. Frustrated by Mari's attempt to escape, Sadie and Francis proceed to beat Mari and Paige as they crawl from the wreckage. Krug attempts to teach Justin to "be a man" by forcing him to touch Mari's breasts. Paige begins insulting him to get him to stop; in response, Krug and Francis stab Paige repeatedly, and Mari watches her friend bleed to death. Krug then brutally sodomizes Mari, during which he pulls off Mari's necklace and throws it away. When he is done, Mari musters enough strength to escape the group and make it to the lake so that she can swim to safety. Krug shoots her in the back as she swims, leaving her body floating in the lake.
A storm forces Krug, Francis, Sadie, and Justin to seek refuge at a nearby house. Justin is the only one to deduce that the inhabitants, John and Emma, are Mari's parents, and intentionally leaves Mari's necklace on the counter to alert them about their daughter. When John and Emma find Mari barely alive on their porch, and the necklace on the counter, they realize that Mari's tormentors are the people in their guest house.
As they try to find the key to their boat so that they can take Mari to the hospital, Francis happens upon Mari, Emma attacks Francis and John kills him. When going after Krug and Sadie, they find Justin holding Krug's gun; Justin gives the gun to John so that he can kill Krug. Sadie awakens and interrupts John, allowing Krug to escape from the couple: After finding Francis dead, Krug realizes that they are Mari's parents. After Emma shoots Sadie in the head, John chases Krug. Justin is stabbed by Krug, but with a combined effort from Emma and John, Krug is knocked unconscious. John, Emma, Mari, and Justin then leave in the boat for the hospital.
Later, John returns to the cabin, where he has paralyzed Krug from the neck down. John places Krug's head in a microwave. As John walks away, Krug's head explodes, ultimately killing him.
