Controlled, distinctive space opera--from an sf grandmaster. In the near future, altruistic heiress Megan Drake assembles a team to build seedships, small, computer-guided, sub-light-speed vessels carrying gene banks capable of recreating superior humans. Her idea: of hundreds of such ships sent out to the stars, a few will discover suitable planets and seed themselves, thus ensuring the survival of humanity (cf. James White's The Dream Millenium). One ship, damaged by a meteorite, drifts for a million years before approaching a habitable planet, whereupon it manufactures a Defender to make repairs and provide guidance. But the malfunctioning computer creates a Defender--immortal, powerful, half-human, half-robot--who has only fragments of memories from each of the five (male) project specialists . . . all of whom were in love with Megan . . . all of whom were in varying degree incapable of consummating the affair. Thus: pure torture to the incomplete Defender, who also (another error) lacks genitals. Even worse, the planet is occupied, by Attack Command robots who've wiped out the previous civilization in preparation for an invasion by their principals . . . who for some reason never showed up. And the robots are just the first of many problems, material and emotional, that Defender must overcome before he can nurture a new human race --while coming to terms with his lonely, sexless, schizophrenic lot. So, despite a blurred, rather perfunctory ending: a solid, thoughtful, involving effort.