Stanley Coe is on trial for beating humanitarian Nick Janus to death two years earlier. The judge finds him guilty but give him a life sentence rather than the death penalty. Furious, Nick's wife Laurel is in the court and screams that Stanley deserves to die for what she did to her husband. She and her friend, Becca Niles, talk to DA Lew Gallo, who says that he did the best that he could given the case they had. Laurel asks him for her husband's belongings from the night he died and Gallo reluctantly agrees.
As Becca helps Laurel out, she asks if she's okay and Laurel assures her friend that she's been clean and sober for the last sixteen weeks. Laurel goes to her car with Nick's things and goes through the box, and finds her husband's eyeglasses. She puts them on the dashboard and then breaks into tears when she finds a watch that she gave to Nick. Recovering, Laurel notices that the lenses of the glasses are glowing and hesitantly puts them on. When she does, Laurel sees herself as Nick, looking at himself in the car's rearview mirror.
Laurel goes home and meets with Becca, and tells her friend what she saw. However, she admits that she hasn't seen anything when she's put them on since the first time. Laurel insists that she's clean and tells Becca to check the house to confirm what she's saying, and insists that Nick was the one who helped her whenever she fell apart. Becca looks around at all of the clippings of Nick's murder that Laurel has collected and tells her to throw them out, get rid of Nick's things, and move on with her life.
Once Becca leave, Laurel takes her friend's advice and starts throwing everything out. However, she sees the glasses flicker again and finally puts them on. She doesn't see anything at first, but when she takes a box out to the garbage, Laurel sees Nick standing next to this car on the night of his murder and then walking inside. She follows him inside and discovers that Stanley, Nick's ex-partner, is waiting for him. Laurel can also hear what is being said and listens as Stanley tells Nick that they have to talk.
Laurel hastily takes off the glasses and goes inside. She uses the glasses again and sees Nick and Stanley arguing. Nick insists that he's under pressure because he had to take Laurel to rehab again, and Stanley accuses him of embezzling from their company. She refuses to leave and when Nick tries to call the police, Stanley grabs the phone and they fight. Wincing in pain as she gets a headache, Laurel takes off the glasses and rubs her head.
The next day, Laurel invites Becca over and explains what she's going through. Becca doesn't believe it and Laurel tells her that it's strange that Stanley and Nick were fighting in the living room when his body was found in the upstairs bathroom. Becca wonders what the point is when they already know Stanley is guilty, but Laurel insists that she has to find out what really happened so she can put it behind her. Becca suggests that they take a weekend off and go to a friend's cabin, and tells Laurel that she'll pick her up the next day.
Laurel goes back inside and discovers that the DA's office has called to say that the court of appeals has given Stanley a new trial. Laurel figures that she can use the glasses to give the necessary testimony and puts them back on. She sees Stanley and Nick struggling, and Stanley finally knocks Nick down and grabs his humanitarian award. However, rather than clubbing him to death, Stanley puts it down and says that Nick isn't worth it. He leaves and Laurel realizes that Stanley isn't the killer.
The next day, Laurel goes to see Gallo but he figures that she's hallucinating due to stress and refuses to reopen the case on the basis of Laurel's visions. Desperate to know the truth, Laurel goes home and puts the glasses on. This time she sees Nick going upstairs to clean up and running hot water in the sink. The door opens behind him and a woman is visible through the steam. Nick smiles and thanks Becca for coming. Becca calls out for real at that moment, and a shocked Laurel goes down to talk to her.
When Becca sees the glasses, she tells Laurel to get rid of them. They struggle and slam the glasses against the wall, knocking a piece out of one lens. Furious, Laurel accuses Becca of sleeping with Nick, and Becca admits that she did. She blames Laurel, saying that Nick was embezzling from his company because he needed enough money that he could get away of Laurel. Laurel accuses Becca of killing Nick and backs away, but Becca insists that Nick was already dead when she found him at the house. She didn't tell the police because then they would have suspected her.
Laurel runs upstairs to the bathroom and locks herself in. She manages to fit the broken piece of lens back into the glasses and puts them on. She sees Nick telling the woman behind him that he's leaving Laurel because he's sick of her constant visits in and out of rehab. The woman steps forward and Laurel realizes that... it's her. She watches, horrified, as the murder replays and she beats Nick to death with his humanitarian award. Shocked, Laurel drops the glasses and they break on the floor. Becca calls the police and they break down the door.
Later, Becca is in a straightjacket in a padded room. She stares off into space, muttering over and over that she was the one who killed Nick.