In the opening scene, as pregnant young Rosie Jones (Emilia Fox) rides on a train, her very large trunk starts leaking blood. When questioned by the police, she calmly reveals that the two dismembered bodies inside are of her unfaithful husband and his mistress. She is then sentenced by the judge (Roger Hammond) to a secure unit for the criminally insane for manslaughter.Forty-three years later, in the village of Little Wallop, Walter Goodfellow, the vicar (Rowan Atkinson) is very busy writing the perfect sermon for a conference, having no idea about the problems in his house, which include the unfulfilled sexual needs of his wife Gloria (Kristin Scott Thomas) who subsequently starts an affair with her golf instructor, Lance (Patrick Swayze); the rebellious nature of his daughter Holly (Tamsin Egerton) who constantly picks up new boyfriends; and son Petey (Toby Parkes) who is bullied by schoolmates. Then everything changes with the arrival of the new housekeeper Grace (Maggie Smith).Walter and Gloria first meet her when they fail to fetch Petey from school and see him strolling with her. Gloria becomes very angry, thinking that Grace is trying to kidnap him and is appeased only when the latter identifies herself by showing an envelope with her name on it. Grace is installed into their lives and learns about some of the problems in the house Clarence, the neighbour's (Mr. Brown's) nuisance-barking Jack Russell terrier, who disturbs Gloria's sleep; the boys who bully Petey; and the golf instructor with whom Gloria is having an affair. Walter does not know anything about any of this - the only problem he has is the toxic blue-green algae in the garden pond. Grace resolves to solve these problems in her own way. She first kills the dog, Clarence, and when his owner finds out that his dog has been killed, she kills him, too. She sabotages the bullies' bicycles, injuring one of them and thereby making Petey very happy. She catches the golf instructor outside the house one night, videotaping Holly undressing, and kills him with an iron. Around the same time, Walter leaves for a Biblical convention.However, Grace is discovered when Gloria and Holly see her picture on the television in a news item mentioning her release and previous offences. It is then that Grace reveals that she is Gloria's long-lost mother, Rosie Jones, explaining why she came to Little Wallop in the first place. Gloria attempts to teach Grace that when having a problem with someone, one cannot just kill them but is baffled when Grace says that that is the one thing she and her doctors could never agree on, implying that Grace's condition is beyond treatment. Despite their disagreements, Gloria tries to help Grace remove Lance's body, but cannot face up to it. Over a cup of tea, the three women decide not to tell Walter or Peter any of what has happened.But all is not over. When nagging congregant Mrs. Parker comes over to discuss the problem of the church flower arranging committee, Grace, under the impression that Mrs. Parker is about to turn them in, attempts to hit her over the head with a frying pan, but is prevented by Gloria. Mrs. Parker, shocked by the murder attempt, has a heart attack and dies. Walter, having just returned from the convention and unaware that she is already dead mutters: "Oh, that flower arranging committee. It'll be the death of her." Soon after this, Grace leaves the family when order seems to be restored among them.At the end of the film, Walter is talking to Bob and Ted, the water works employees, about the pond at the Vicar's house. They say that there is too much algae and the pond needs to be drained. Gloria knows that Grace disposed of her victims in the pond. Gloria, with a disturbingly cheerful expression ("Shall I put the kettle on?"), offers the two men some tea, the film closes with an underwater shot depicting the bodies of Bob and Ted in the pond.
Is Lance's daughter of the age of elementary school?