Crop circles first appeared in the 17th century and have been increasing in both size and complexity, particularly in the last part of the 20th century. They are now appearing all over the world and on ice as well as in corn fields. Lucy Pringle has been studying this phenomenon during the 1990s and has photographed each new circle. She has also studied the different impact that the circles have had on the people that have visited them and the effect on animals and machinery in the local area. Strangely, many people and much of the world media are happy to believe that the circles have been produced by a skilful team of hoaxers or even hedgehogs. But when you examine the circles themselves, the scale, geometric precision and quality of the corn, make the idea of a human team of hoaxers a little hard for the rational mind to accept.