Clayton Donner, son of an asteroid-belt mining family, gets sent to Earth for university. At UCLA he befriends Slvia Rollan, only child of rich, reclusive, inventor Dr Ludwig Rollan, and is invited to stay at his home on the Hoop, an Earth-like space habitat powered by a black hole. On Hoop Clayton discovers Dr Rollan's strange experiments in creating a new human society, but all is not what it seems....A good story with too much packed into it. ( )