Plot
In Phoenix, Arizona, 18-year-old wrestler Robert "Bobby" Tennison starts talking to 16-year-old classmate Stacy Collins. He eventually invites her and her friends to a late night lake party. There, Bobby and Stacy sneak off, and eventually learn that their fathers abandoned them.
Meanwhile Stacy's mother, Laura, is dating Rod Merredi, who is emotionally abusive.
Bobby eventually starts showing possessive behavior. He wants Stacy to always be home at night when he calls and not hang out with anyone when they are together. He occasionally apologizes after getting mad at her, says that he loves her, and gives her gifts.
While shopping with her friend, Nicki, Stacy reveals bruises on her back. They come from the night she lost her virginity to Bobby. At school, boys start to notice her after Nicki convinces her to wear a mid-thigh length skirt. Eventually, a boy compliments her. Outraged, Bobby later says that she looks like a slut and forces her to wear pants for the rest of the day. After she says that she was only dressing up for him, he slams her into a wall. His school coach, Murphy, considers reporting the incident, but Stacy defends hum by saying that she "slipped".
Stacy starts missing events because Bobby has limited her time with friends. Nicki learns that his previous girlfriend, Tracy, changed schools after being hit by him. Nicki later notices more bruises on Stacy's arm. Stacy, frustrated, says that she can take care of herself.
Stacy later bumps into Bobby's mother, Rita, whom he forbade her to meet. After catching them talking to each other, he slams her into a truck. Upset, she refuses to see him again. He, however, sneaks into her house after Laura goes out with Rod. He coaxes her back into a relationship by relating to her with stories of his estranged father, who was an abusive alcoholic.
They later attend a school dance, where Bobby eventually sees Stacy talking to another boy. He pulls her into the parking lot and slaps her.
Nicki gets worried, but Stacy defends Bobby, saying that he has been through a lot. Returning home, she hears Laura arguing with Rod and decides to stay at Nicki's. Laura ends things with Rod that night.
Stacy breaks up with Bobby as well. Carla, a mutual friend who is in love with him, tries to make plans with him. He takes advantage of this opportunity to offer to pick Stacy up and have her hang out at his place. He invites Carla too. There, he accuses Stacy of being with another boy and slaps her.
In private, Bobby kisses Carla and says that if anyone asks, he and Stacy fought and she left.
Later that night, Bobby, accompanied by his friend, Vince Fortner, convinces Stacy to take a ride in his car. He drives them to the lake and walks off with her while Vince waits in the car. The next day, it is reported that she is missing.
Laura and Nicki go out looking for Stacy. Laura suspects that Bobby was involved in her disappearance and finds her purse in his room. Pretending to be concerned about her, he enlists people to help look for her. Meanwhile, Nicki interrogates Carla, who repeats what Bobby told her to say. Nicki eventually informs Laura and Detective Anderson how abusive Stacy's relationship with Bobby was. Carla later admits that he and Vince took her to the lake.
Bobby and Vince get arrested, and Bobby blames Stacy's disappearance on Vince. After admitting that Bobby was the one last seen with her, Vince is free to go. Anderson intially gently tells Bobby he suspects voluntary manslaughter, and will help Bobby out if he cooperates, but Bobby refuses to admit to anything. Anderson cracks down and furiously demands answers from Bobby, who finally realizes there's no way out and admits that he slit Stacy's throat when she refused to resume their relationship, meaning he killed her.
Stacy's body is found in the lake, wrapped in a trash bag bound with duct tupe and tied down with cinder blocks. A court trial follows, where lots of classmates admit that they saw Bobby hit Stacy but did nothing figuring that she would leave him eventually. He is eventually found guilty of first-degree murder, and sentenced to life in prison without parole. The judge then gives Stacy's classmates a stern lecture about their inaction in witnessing her abuse. Later on, Nicki and her boyfriend Tony leave flowers at the edge of the lake where Stacy's body was found.
