Ten-year-old Devon Stockard, [Mischa Barton], a precocious and lonely girl, has recently moved into the gated community Camelot Gardens in the Louisville, Kentucky suburbs with her parents, Morton [Christopher McDonald] and Clare [Kathleen Quinlan]. Recently recovered from open heart surgery, Devon is encouraged by her parents to make friends, and is pushed to sell cookies for a charity event for the summer.
While selling cookies, Devon leaves the gated community against her mother's instructions, and meets Trent Burns, [Sam Rockwell], a landscaper living in a trailer in the woods, who works in Camelot Gardens. Devon, at first annoying Trent, continues to come to his property and slowly befriends him. Despite the innocence of their friendship, he insists that she keep it a secret because of their age difference.
While working in Camelot Gardens, Trent has altercations with two young men who live there; [David Barry Gray] Brett, who is fooling around with Devon's mother; and [Eric Mabius] Sean, a closeted homosexual who flirts with him. During a family barbecue, exploring her father's car in their garage, Devon finds his handgun in the SUV's glove compartment. Brett discovers her with it and attempts to molest her, but she escapes. Telling her parents about the incident, they respond by stressing over the social implications and how influential Brett's father is. So, Devon changes the story to that Brett was only trying to tickle her.
Clare begins to notice Devon's friendship with Trent when he comes to do lawn work at their house and becomes alarmed. Meanwhile, Brett and Sean vandalise Trent's lawnmower, pouring sugar in the fuel tank and start a fight with him after accusing him of stealing CDs from Sean's car.
Devon and Trent's friendship grows, and they visit Trent's mother [Beth Grant] and his father, a Korean War veteran dying of a lung disease [Tom Aldredge]. After leaving their house, Trent and Devon go for a drive in the country. While stopped in a field, she insists that as they are best friends, she can show him the surgical scar on her chest. Insisting he touch it to his reluctance, she then demands he show her the abdominal scar he sustained in a shooting, which she touches as well. After this, they see Sean's escaped dog, running through the field. While trying to chase it down in the truck, they accidentally run him over. Trent kills the badly injured dog although Devon pleads with him not to, and she runs home in a panic.
Clare and Morton, concerned over Devon's frantic behavior, ask her what happened. She won't provide details, only saying that Trent killed Sean's dog and mentions she and Trent took turns showing each other their scars. Assuming that Trent molested her, Morton drives out to Trent's property with Devon, assisted by Sean and the ex-cop security guard of Camelot Gardens. The three confront Trent while Devon sits in the car.
Morton and Sean take turns beating Trent, and Morton accuses him of sexually abusing Devon. He attacks Trent with a piece of wood, beating him to the ground, handing it to Sean; but before he can hit him, Devon exits her father's car with his gun, shooting him in the abdomen. As Sean bleeds on the ground, Devon urges Trent to leave, and they say their goodbyes.
Armed with her father's gun, Devon orders her dad to lift her up into the tree she and Trent had decorated with ribbons, and she imagines a river and a forest rising up behind Trent as he drives away, protecting him as he escapes.
