Lieutenant Melora Pazlar, first seen in the Deep Space Nine episode that bears her name (Melora), is the only Elaysian in Starfleet. While stationed on board the U.S.S. Enterprise, six years after her aborted romance with Dr. Julian Bashir, she is contacted by a member of a telepathic race from her crystalline, multi-species homeworld. Although Gemworld is independent practically to the point of isolationism, Melora and Troi agree that it is clearly a desperate call for help, and when subspace contact proves to be impossible, Picard orders the Enterprise off course to investigate.
Coming out of warp near the planet the Enterprise is nearly torn apart by a dimensional rift not on its charts, and is stranded, badly damaged, below the shields that protect the carefully constructed planet. The singularity makes escape or rescue impossible, and Picard and crew set out to discover the cause of the rift and of the strange, cancerous growth in the crystal choking the planet itself. A Federation rescue ship attempts to reach the Enterprise but is destroyed, thoron radiation may kill the crew in eight days or less, and all signs on the planet point to sabotage!