The well-meaning but rather dull Reverend Walter Goodfellow, vicar of Little Wallop, spends all his energies on his sermons. As a result he fails to notice the unsuitability of his daughter's boyfriends, his son is struggling to make any friends at school and his wife conducting a half-hearted affair with her suave golf teacher Lance.

But everything changes when the Goodfellows get a sweet new housekeeper, Grace Hawkins. However, it soon transpires that in her spare time Grace is a psychopathic serial killer, and she is using her 'hobby' to rid the family of those causing them problems!