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 provisional Bajoran government, Starfleet stepped in to oversee the rebuilding and day-to-day operations of the newly christened Deep Space Nine. DS9 soon became a center of travel and commerce thanks to a newly found stable wormhole leading to the largely unexplored Gamma Quadrant.
Kira and O'Brien try to rescue a famed Bajoran resistance fighter from a Cardassian slave-labour colony in an attempt to bring peace to the warring Bajoran factions.
After she is relieved of her post aboard, Deep Space Nine, Kira tries to expose the leaders of the terrorist group known as 'The Circle.'
Sisko is forced to evacuate the station when the war escalates and turns in favor of the terrorists.
An unjoined trill kidnaps Jadzia and removes the Dax symbiont to implant into himself.
A custody battle emerges over an orphaned Cardassian boy who was raised by Bajorans.
Bashir falls in love with a wheelchair-bound woman, who is unable to walk in Deep Space Nine's level of gravity.
A female Ferengi disguises herself as a male in order to help Quark with business deals in the Gamma Quadrant.
Quark is injured in an attack which Odo suspects is related to a murder committed five years before, in which Kira was the prime suspect.
For the first time since the death of his wife, Sisko falls in love. However, his new interest seems to suffer from a bizarre form of split personality.
A group of refugees from the Gamma Quadrant claims that Bajor is their long-lost homeland.
A con artist opens a bar with a gambling machine that can alter the laws of probability.
Dr. Mora Pol, who first studied Odo as an infant, announces that he may have found Odo's homeworld in the Gamma Quadrant.
Bashir and O'Brien come under attack from the people they are trying to help on a warring planet.
O'Brien returns from an away mission to discover that he has been locked out of every security system on the station, and that everyone has turned against him, including his wife.
Sisko and O'Brien are stranded on a planet with a human colony that has forbidden all forms of technology.
Odo and Dax discover a planet where the inhabitants are disappearing.
While hosting a Trill initiate, Jadzia discovers a new universe growing from protoplasm in the science labs.
Quark puts everything at stake to win back his long love Natima Lang, a Cardassian woman suspected of terrorism on Cardassia.
Jadzia Dax honors an oath made by Curzon Dax to a group of Klingons, and goes with them on a crusade against their sworn enemy.
Federation colonists reject a treaty with Cardassia and take matters into their own hands, forming a terrorist group called 'The Maquis'.
Sisko's friend, Commander Cal Hudson, resigns from Starfleet to join the Maquis in their fight against the Cardassians.
In order to save Garak's life, Bashir must unravel some of the secrets in the Cardassian's past.
An accident, which occurs while traveling through the wormhole, leaves Kira and Bashir stranded in an alternate universe where humans are slaves.
Kira discovers that the man she loves, Vedek Bareil, may have been responsible for the death of 43 Bajoran freedom fighters.
O'Brien is found guilty and later tried at a tribunal held on Cardassia Prime.