A series of murders unfolds in Midsomer Parva with the discovery of a naked body in the center of a mysterious crop circle in a field owned by Sir Harry Chatwyn. When local extra-terrestrial expert Lloyd Kirby becomes interested, rumors abound that the vicious death could be the work of some alien force. Barnaby, however, has other ideas when the bodies of a local criminal and Sir Harry's adulterous son-in-law are found under extraordinarily similar circumstances. Barnaby's investigation reveals multiple motives and multiple killers who used the first murder as a model for their own deadly endeavors. Guest star: John Woodvine (Doc Martin; Nicholas Nickleby)