Earth's first space colony is in crisis. All but 16 of its 128 men have been rendered infertile in-flight to the planet they call Nova Terra. To save their future, the 128 women agree to be impregnated by the remaining 16 "sperm-fathers", and each man agrees to impregnate 32 different women. The relationships and traditions of this new colony change in response, but when their kids grow up, they have quite a different opinion.