Set in the future when Earth has become heavily over-populated, advances in space travel led to the discovery of Eden, an earth-like planet. Colonisation is progressing but the majority of the settlers are men and the need for more women has become urgent. Some willing women are persuaded to move to Eden to redress the balance. Beth is one such woman who has elected to live with four brothers. Each brother is uniquely different. The eldest, Luke, has emotional scars and maintains a discreet distance, which only draws Beth closer. The Eden natives are feline in appearance, affectionate and fun-loving. They have no discernable language or technology and are regarded merely as highly developed animals. They are particularly drawn to Beth and with their aid, she manages to solve the riddle Luke represents.