A banal affair becomes something more sinister and tragic than a FATAL ATTRACTION when there's A WOLF AT THE DOOR. When housewife Sylvia (Fabiula Nascimento) goes to pick her daughter Clara (Isabelle Ribas) up at school only to discover that she has been taken by someone who said she was a family friend, she is terrified and convinced that the kidnappers must have taken the wrong person she and her bus inspector husband Bernardo (Milhem Cortaz, EMBODIMENT OF EVIL) are poor people. Bernardo, however, has no doubt as to who is responsible, confiding in the police inspector (Juliano Cazarré, ELITE SQUAD) his affair with pretty Rosa (Leandra Leal, SUNSTROKE). He tells the inspector of how they carried on their affair with Rosa fully aware that he had no plans to leave his wife and daughter, but that she started getting possessive and frightened him by buying a gun to carry around in her purse. He then describes how his wife Sylvia told him that she had made a friend by the name of Silvia who turned out to be Rosa posing as a friend of a high school friend. Upon questioning Rosa - who Sylvia confirms is Silvia and positively identified by the schoolteacher as the woman who picked up Clara - she tells the inspector that she had been blackmailed into picking up Clara to give a Bernardo a scare by an angry woman named Betty (Karine Teles, MADAME SATA), not realizing that she was being set up to take the blame for the disappearance. Although Bernardo offers up some proof that Betty exists - as the woman he believes Rosa paid to call and try to convince him that Sylvia was having an affair - they are unable to find the woman. When the inspector puts the screws to Rosa, she offers up a different version of her affair with Bernardo who at first told her that he was unmarried and lived with her mother, and then became possessive when she confronted him and tried to dump him. Her story seems more believable in that she admits that she befriended Sylvia and tried to alienate the couple from one another, and that Bernardo was wishy-washy about whether he wanted to stay with Sylvia or run off with her; but the affair culminates in such a horrid manner that, if true, it might offer up a motivation for the child to disappear.