We watch a street, and in front, a middle-house home. Suddenly, we hear the voices of two people, and the images move back. The comments lead us to know the situation.
Georges Laurent (Daniel Auteuil) is the presenter of a literary TV programme. The programme is going well and he's got many fans, especially female. He's married to Anne (Juliette Binoche). The couple has just received a mysterious video tape: for two hours somebody has recorded the street and the front of their home. We can see several passers-by, a biker, and Georges leaving for work. The tape had no other message, it appeared just inside a supermarket white plastic bag.
The next day, the couple receives another tape. This time it's a night shot. The same as before, nothing much seems to happen. However, this time the tape was wrapped in a plain paper with a child-like drawing of a boy's face stained with blood. The couple decide to go to the police, but they will not do anything about it, because there has been not actual thread. None of the neighbours of the side street from where the camera must have been placed has seen anything or anybody, in spite of the recording lasting for more than two hours. When they leave the police station, deeply frustrated because of the lack of attention to the problem, Georges crosses the road without looking and has a verbal fight with a biker (Dioucounda Koma) who almost crashed onto him. It's Anne who has to tell them to calm down.
Little by little, we see Georges' life: he leads his programme proffesionally; he's got a good social life, and his son Pierrot (Lester Makedonsky) goes to high school and belongs to the swimming team. In fact, he wins the swimming competition Georges and Anne attend as spectators.
During a dinner with some of their friends, Georges goes to attend the door. Although it's really late, somebody has just rung the bell. When Georges goes out, there is nobody there. He shouts to the dark empty street "Show up, you coward". When he tries to close the door, he can't, because there is another tape on the floor. Anne tells their friends their present problems, to which Georges responds - really annoyed - by showing the new tape to everybody. This new tape shows somebody driving on a rainy road, through the countryside. The car stops and the camera turns to face a countryside manor mansion. This tape is wrapped in a paper with a child-like drawing of something similar to a hen with its neck bleeding.
Georges goes to that manor house: it's the house where he grew up. His mother (Annie Girardot) is old, and needs help because she can't take care of herself. Georges doesn't like the housekeeper (Marie-Christine Orry), but he won't do anything about it.
The reception and the vision of the tapes is intertwined with some images, some flashbacks of a boy bleeding through his mouth (Malik Nait Djoudi). Although Georges says that he doesn't know anything about the tapes or why they are being sent to him, little by little the viewers come to realise that these images are flashbacks.
We finally come to know that Majid was a child Georges' parents adopted, but somehow he was sent back to the orphanage. Georges' mother doesn't want to talk about Majid, but we don't know up to what point she can't remember.
The next tape happens again inside a moving car. Anne discovers the name of an avenue, and Geoges used that to find a particular door, number 049.
Georges go there on his own in spite of Anne's disapproval. There, he finds a surprised and sad man. Although Georges doesn't recognise him at first, that man recognises him. It's Majid (Maurice Bénichou), the Algerian boy Georges' parents sent back to the orphanage, now a sad forty-yeared-old man. In the following conversation, the adult Majid denies to know anything about any tapes. He says that once, watching Georges by chance on TV, felt disgusted and about to throw-up. Georges talks to him in a cocky and aggresive way. He storms out.
The next day, Anne sees at home the camera images of Georges talking to Majid. Majid was left for an hour, crying devastated, sat on a chair. As usual, everything had been recorded onto a tape. Georges says he doesn't feel responsible for Majid's loser life or for having taken away his possibilities of leading a priviledged life like his. He tells the story: Majid's parents were servants at Georges' parents' home. They went to a demonstration in Paris. At that demonstration, the police killed 200 people and threw their bodies to the River Sena, among whom both of Majid's parents were. Georges' parents adopted Majid, but Georges - at that time 6 years old - (Hugo Flamigni) felt jealous of having to share everything. He tells Majid to kill a rooster and he does so, beheading the poultry with an axe. Georges tells his parents that Majid did that to scare him.
The tape was not only sent to Anne. Georges's boss (Bernard Le Coq) received the tape with a postcard with a drawing on the fashion of the rest of the paper drawings. His secretary spot the weird message and gave it to him. Talking about another programme which is taking longer to take off as an introduction, the boss explains the situation to the surprised Georges, who admits he looks really aggressive in that tape. The boss had destroyed the tape because it went against Georges' privacy and he doesn't want any scandals.
Another event puts the Laurent family even more on edge: Pierrot has disappeared. Anne phones Pierrot's best friend, but he's not there. Anne and Georges phone the police. The police officers (Loïc Brabant) go to Majid's home, but somebody else, a younger man, opens up the door and lets them in. It's Majid's son (Walid Afkir). Everybody goes to the police station to be questioned.
Suddenly, Pierrot appears back home with another woman. It's a nurse (Caroline Baehr). As she works the night shift, she doesn't usually know what his own son -another of Pierrot's friends- is about. Later, Anne tries to talk to Pierrot and asked why he had given them such a scare. Pierrot doesn't want to communicate at all, but one of the few things he says is that he thinks that his mother and one of her friends, Pierre (Daniel Duval) are lovers. Anne rejects that notion.
Georges is called by Majid, so he comes back to is flat. When questioned on the reason, Majid says that he wanted Georges to see that. He takes a pocket knife from one of his pockets and cuts his own throat. He falls to the floor completely dead.
Georges phones the police. The police believe Georges and realises that it was suicide. The next day, Majid's son visits Georges in his office. He says that he wants to see his guilty face and leaves without more ado.
Georges comes back home and is alone. He takes some pills and goes to sleep. In his dreams, or in a flashback, he sees how an orphanage attendant (Paule Daré) and an orphanage driver (Nicky Marbot) who take Majid away to the orphanage by force in spite of the boy screaming his lungs off. Georges's mother (Annette Faure) watches all this nonchalantly.
The last scene is a fixed shot of a camera of the stairs outside Pierrots' high school. He is talking and laughing with Majid's son.