[Quantum physics and space-time relativity are explored at length in this densely packed hard science fiction story.] On a planet circling a black hole ninety-seven light years from earth, five physicists are preparing an experimental ship to descend into a nearby black hole. The crew for the suicide mission will be the physicists' clones, and although the originals don't expect the crew to survive or send back information about the structure of spacetime at the Planck scale, they are secretly hopeful their genetic counterparts will prove them wrong.