Farmer Geraldine Merrick suspects vandalism when crop circles appear in her wheatfield and plans to harvest immediately but widowed ufologist Terry is convinced it is the work of aliens and a site of scientific interest, requesting Peter to stop her.

Cast: Sandi Toksvig, Stephen Fry, Karl Davies, Neil Dudgeon, Hermione Norris, Celia Imrie, Colin Baker, Pax Baldwin, Kate O'Flynn, Thomas-James Fisher, Damian Kell, Richard Frame, Amy Marston, Gerard Horan, Tony Slattery