In literature, television and film, the eyes are often imbued special meaning; the idea that you can tell something about a person, or what they are thinking or feeling, by gazing into their eyes. Eye colour is often considered a very straight-forward trait, with eyes being either brown, blue or green. But it is easily apparent that there is far more variation in human eye colour than that allows for, and that its inheritance is not always what one might expect. There are even some people out there who will try to convince you that your eye colour is controlled by diet. What really controls the appearance of our eyes? What are our eyes saying about us?