Cris Sarast finds herself hopelessly marooned in a place bereft of other human beings, a planet similar to the Earth 100,000,000 years ago. She is devastated that, after her long journey, she can find no sign of the civilization she believes must be present. Adding to her distress is the lack of any communication from her lover who had preceded her by three years. She learns to survive but soon makes two shocking discoveries: she is inexplicably pregnant and a navigational error has put her in the wrong place. Since there is no escape and no rescue possible, she and the fraternal twins she bears are marooned for life. Eventually, her children reach sexual maturity and, as human nature would have it, both Cris and her daughter become pregnant by the only available male – her son Aron. The resulting life-threatening conflict is resolved by their love of life and each other.