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.
Sisko is assigned the mission of taking the Defiant into the Gamma Quadrant to make peaceful contact with the founders of the Dominion.
Odo begins to connect with his fellow Changelings as Sisko attempts to negotiate peace with the Dominion.
Quark lies about killing a Klingon and is then forced to marry the widow.
A secret from Dax's past could mean the end of the current host's life.
Kira is abducted and altered to look like a Cardassian in order to frame a Cardassian politician.
A Jem'Hadar infant is found in salvaged spaceship wreckage and Odo strives to teach the rapidly maturing soldier to think for himself.
Deep Space Nine is progressively locked down after O'Brien, Jake and Sisko accidentally activate an old automated Cardassian security program.
Jadzia falls in love with a scientist on a planet whose inhabitants shift between this universe and a plane of pure energy every sixty years.
When Commander William T. Riker from the Enterprise arrives on Deep Space 9, he takes a liking to Kira, who gives him a tour of the Defiant. But Riker is revealed to be not who he claims to be when he attacks Kira and steals the ship.
Lwaxana Troi pursues Odo during the Bajoran Gratitude Festival as members of the crew suddenly become infatuated with one another.
A transporter accident sends Sisko, Bashir and Dax three centuries into Earth's dark past.
Sisko assumes the role of a pivotal historic figure in order to restore the timeline.
Bashir's ethics are put to the test as he keeps Vedek Bareil alive long enough to help Kai Winn complete negotiations for a peace treaty with Cardassia.
Searching for a Maquis raider on an unstable moon, Kira is trapped in an expanding crystal formation that threatens to engulf her if Odo cannot set her free.
Despite a Bajoran prophecy of destruction, Sisko assists in a joint scientific venture with the Cardassians to open communications through the wormhole.
In a shock revelation to Quark and Rom, the Grand Nagus reveals he has re-written the Ferengi Rules of Acquisition; a move which threatens to cripple the Ferengi Empire.
Exposure to radiation causes O'Brien to jump hours into the future for brief periods, as Deep Space Nine hosts Romulan and Klingon delegations.
After an alien assault leaves Bashir unconscious, he is trapped inside his mind.
Sisko is abducted by the Miles O'Brien from the mirror universe, and is forced to assume the identity of their Sisko in order to rebel against the Klingon-Cardassian Alliance.
Garak's tailor shop is bombed, forcing Odo to investigate who is trying to kill the Cardassian exile.
Garak must decide whether or not to kill Odo to please his mentor on the eve of a joint Romulan-Cardassian attack on the Dominion.
Sisko and Jake build a solar sailing ship in an attempt to recreate a journey taken by the ancient Bajorans.
Quark returns to his home planet to confront his mother after hearing from the Ferengi Commerce Authority that she broke the law by earning profit.
Kai Winn needs Kira to convince her former resistance leader, now a farmer on Bajor, to return soil reclamators needed elsewhere.
Jadzia Dax deals with feelings of inferiority as she encounters past hosts in a Trill ceremony.