A passenger aboard an arriving freighter who is suffering from Kalla-Nohra, a sickness that could only be contracted at the Gallitep forced labor camp on Bajor when a large mining accident occurred, is beamed to Deep Space Nine's sickbay. Major Kira goes down to meet the survivor of the camps... only to find that the person suffering from the sickness is a Cardassian.
When the Cardassian occupation of Bajor ended in 2369, the mining space station Terok Nor was left abandoned, its systems ripped out. By invitation of the Bajoran provisional government, Starfleet stepped in to oversee the rebuilding and day-to-day operations of the newly christened Deep Space Nine.
The years of Starfleet's nonintervention into Cardassian matters, however, had taken its toll on relations with the Bajorans. Consequently, Starfleet's position was a tenuous one; many Bajorans, suspicious and hostile as a result of decades of Cardassian oppression and brutality, did not greet the Federation's presence with open arms. The Federation's assistance is put to the test as DS9 becomes a center of travel and commerce that stretches into the Gamma Quadrant.