Sixteen-year-old Clarity "Clare" Fern lives in the small tourist town of Eastport on Cape Cod with her mother, Starla, and her brother, Perry. Clare is a psychic (she receives visions when she touches objects), Perry is a medium (he can hear and sometimes see spirits of dead people) and Starla is a telepath (she hears people's thoughts). Clare and her family conduct psychic readings at their home near the beach. Most of the family's business comes from the tourists visiting the area, and the summer is the Fern family's busiest season.
While doing a reading, Clare's neighbor walks into their living room and announces that a teenage girl was found murdered in a motel room. Everyone is shocked because a serious crime is rare in Eastport.
That same day, Perry and Clare meet their friend Nate for lunch. Nate tells the siblings that new police detective Anthony Toscano and his son, Gabriel, have moved to town. Anthony will be leading the murder investigation.
The day after the murder, Clare's mother gets nervous because tourists are canceling their appointments and leaving town. Additionally, a new psychic, Madame Maslov, has moved to town and is competing for their already dwindling business. Madame Maslov advertises that she can tell the future, something that the Ferns do not believe in because the future is constantly changing due to decisions people make every moment. Clare thinks Madame Maslov is a fraud.
Justin, Clare's ex-boyfriend and the mayor's son, comes to the house to see Clare. He gives her details about the investigation and tells her about the victim, Victoria. Justin asks Clare to use her psychic ability to help the police solve the case. (A few months earlier, Justin cheated on Clare, and she is still angry with him.) Despite not wanting to help Justin, Clare feels a sense of duty and obligation to help find Victoria's killer.
Clare and her family go to the boardwalk to check out Madame Maslov's business. They see one of Perry's classmates, Stephen Clayworth, walking out of the psychic's shop. Stephen's parents are the richest people in Eastport, and his father, Dallas Clayworth, is running for mayor. During the school year, Stephen started a fight with Perry over a girl, which angered Clare, so she told a teacher that Stephen had cheated on a test. She saw him do it in a psychic vision. Clare's tip almost cost Stephen his spot at the Ivy League college he will be attending in the fall.
On the boardwalk, Stephen gets into an argument with Clare and Perry, but Stephen's mother, Cecile, breaks it up. She apologizes and calms Stephen down. The Clayworths leave, and Clare and Perry talk.
When Clare mentions Victoria's name, Perry tells her that he met Victoria at a restaurant. Then he took her back to her motel room, and they had sex. Perry tells Clare that Victoria was alive when he left her. Clare decides to protect her brother by not telling the police what she knows and to concentrate on catching the killer before Perry becomes a suspect.
The mayor asks Clare to work with both Justin and Gabriel to solve the murder because the police can't be seen working with psychics or teenagers. Clare meets the boys to start work on the case, and Gabriel is annoyed. He does not believe in psychic abilities and does not like being forced to work with Clare. Clare, in turn, does not like being considered a fraud and despite her attraction to him, tells Gabriel that they should solve the case quickly so they don't have to see each other again.
Gabriel takes Clare to the crime scene at the motel where she notices a hole in the ceiling that gives the person in the room above a clear view of the bed. Clare also sees a vision of Victoria getting shot, but it's too dark to see the killer.
The next day, a girl named Joni comes to the Ferns for a psychic reading, and Clare discovers she is Victoria's best friend. Joni had an affair with Victoria's boyfriend. When Victoria found out, she came to Eastport for the weekend. Clare and her mother try to convince Joni to talk to the police, but she is scared of Victoria's boyfriend, Joel, who has a bad temper. Hoping that Joel was the killer, Clare sends a text message to Gabriel and the police to come to the Fern home to take Joni in for questioning.
Later, Gabriel meets Clare for lunch and tells her that Joel is now the main suspect, but they are also looking for a young man named Billy, the motel's maintenance person, who was staying in the room above Victoria's. Billy has been missing for a few days, and Clare agrees to help Gabriel look for him at the town's big fireworks show later that night. While at the beach looking for Billy, Stephen stops Clare and apologizes to her for his earlier behavior.
When the police find Joel, he has an alibi; he is no longer a suspect. Billy is still missing, but when Clare and Gabriel visit Billy's parents' house, they find remains of a note indicating Billy saw the killer and is blackmailing the person. Using the location of Billy's cell phone signal, the police track him down and find him dead in his car.
The police get a tip that Perry was with Victoria before she was killed. They take Perry in for questioning and search the Fern home. They find the security video from the restaurant where the couple met. Perry stole the video from the restaurant so the police wouldn't see him and Victoria leaving together. Mayor Spellman arranges for a lawyer for Perry.
As Perry is waiting for his lawyer, he assures Clare that he is innocent. After leaving the police station, Clare is upset so she goes to the beach where she sees Gabriel. He tries to console her. While they are on the beach, the dead body of a girl washes up. Clare touches the body and sees a vision of the girl being strangled. Gabriel pulls her away and tells her the body is Joni, Victoria's best friend. Gabriel believes that Perry is the real killer, and he and Clare argue. She leaves him on the beach.
Clare meets Justin and asks him to help her see a copy of the security video that Perry stole. Mayor Spellman arranges for Clare to view the tape in his office. Clare and Justin watch the tape and see people going in and out of the restaurant, including Cecile Clayworth, who was wearing a green dress. On the video, Cecile goes into the restaurant and leaves with Stephen, who appears to be drunk. The mayor tells Clare that Perry has been released because the police have no real evidence against him.
Knowing that Stephen was at the same restaurant as Victoria on the night she died, Clare calls Stephen and asks him to have dinner with her. He agrees. While at dinner, Clare asks Stephen if he remembers anything from the night of the murder. He tells her he does not because he was drinking. Clare convinces him to take her back to his house. She knows his parents are not home and uses the opportunity to go into Stephen's parents' room where she touches the dress she saw Stephen's mother wearing on the security footage. Clare sees a vision of Victoria sitting at the restaurant bar and appearing to rebuff Stephen's advances. In the vision, Clare also senses intense anger toward Victoria, along with feelings that Victoria was going to ruin everything and take away all that was worked for. Clare believes Stephen is the killer; when he catches her in his parents' room, she runs from him and into the woods across from his house where she calls Justin to pick her up.
Justin takes Clare home, and they find Gabriel waiting for her. After talking to the boys about her vision, Clare realizes that the angry thoughts she picked up were from Cecile and not Stephen. Gabriel tells Clare and Justin that Cecile is the witness who reported seeing Perry with Victoria. Now convinced Cecile is the killer, Clare and Justin beg Gabriel to persuade his father to bring Cecile in for questioning.
Early the next morning, Justin calls Clare and tells her that Cecile is at the police station being questioned. Clare and her mother go to the police station where they are told that Cecile has not confessed, but the Clayworth home is being searched for a murder weapon.
Justin takes Clare back home where Clare sees Perry's unconscious body on the kitchen floor and Stephen with a gun. He points it at Clare and tells her and Justin that he plans to kill them both and frame Perry for the murders. In an effort to protect Clare, Justin charges Stephen and gets shot. Stephen tells Clare that his father had an affair with Victoria, who threatened to go public, which would cost Dallas Clayworth the election. Clare's vision was not of Stephen making advances toward Victoria, but of him trying to reason with her. Victoria would not listen to either Stephen or Cecile, so Cecile went to Victoria's motel room and shot her. Billy saw Cecile commit the murder and tried to blackmail her, so Cecile had Stephen kill him. Joni tried to find out who killed her friend and got too close to the truth, so Stephen strangled her.
Just as Stephen is about to shoot Clare, Perry regains consciousness and wrestles the gun from Stephen. The police arrive just in time and arrest Stephen. Justin has surgery and survives the gunshot wound. Clare finds out that Madame Maslov had a vision just prior to the attack and told the police to go the Fern's home, which saved their lives.