In an Italo-Australian community in Cider Gully, up-country Australia, lives Maria, a 16-year-old teenager in search of her identity. She does not accept her name and calls herself Mars. Her parents would like her to get married as soon as possible. Her dates, however, are so disastrous that she swears to herself that she will never find a husband. All she can think of is to study and become a lawyer. Her mother, Grace, very much repressed by a violent husband, gives her no peace. The grandmother is more understanding, but none will listen to her. Mar feels she is a prisoner in her own house and in a small town ravaged by a plague of flies. Under pressure from her family who doubt she is still a virgin, and through her own will, Mars decides to defy the tyrannical power of the father to gain the right to follow her own destiny.