The entire seventh season of this spin-off series. In 'Image in the Sand', Sisko discovers some dark secrets from his past after experiencing a vision of a woman's face buried in the sand. Meanwhile, the widowed Worf determines to win a battle in Jadzia's honour in order that her spirit can ascend to the Klingon afterlife. Ensign Ezri, the new Trill host for Dax, struggles to make the necessary adjustment. In 'Shadows and Symbols', Sisko journeys to Tyree in search of the Orb of the Emissary, but his actions have devastating consequences.
In 'After Image', Ezri Dax struggles to cope both with the reactions of crew members who remember Jadzia and her new job as ship's counsellor. Her first assignment in the latter capacity sees her forced to cheer up Garak, the Cardassian agent who is suffering from depression. 'Take Me Out to the Holosuite' sees Sisko forced to assemble a Deep Space Nine baseball team when he is challenged to a game by an old sparring partner. Sisko and his ragtag bunch have just two weeks to get in shape...
In 'Chrysalis', Bashir forms an intense personal relationship with a young woman on whom he has carried out untested brain surgery, but the emotional pressure he places her under causes a regression. 'Treachery, Faith and the Great River' sees Weyoun placing himself in Odo's hands when he seemingly defects from the Dominion. DS9's security officer has his initial suspicions allayed by the discovery of a secret relating to Weyoun and the Founders. In 'Once More Unto the Breach', Worf is pleased to welcome an ageing Klingon to the crew when he offers his services against the Dominion. However, Worf finds himself deployed on a suicidal mission as a result. 'The Siege of Ar-558' sees the Starfleet officers experiencing the hardships of war first-hand when the Defiant comes to the aid of a depleted unit on the front line. In 'Covenant', Kira is captured by the followers of the Pah-wraiths and taken to space station Empor Nok. There she meets Gul Dukat, who is attempting to disguise his darker side while posing as a religious convert. 'It's Only a Paper Moon' sees Nog returning to DS9 to convalesce after a serious injury. However, he slides into obsession after witnessing the holosuite club act of crooner Vic Fontaine. In 'Prodigal Daughter', Chief O'Brien goes missing on a mission to infiltrate the Syndicate. Ezri Dax attempts to engage the assistance of her estranged family, who are powerful figures in the local business community. 'The Emperor's New Cloak' finds Quark and Rom on a mission to rescue the kidnapped Grand Nagus Zek, but all does not go according to plan. In 'Field of Fire', the DS9 crew find themselves searching for a serial killer after three officers are murdered. Ezri Dax finds clues in her own past to the killer's next move, and realizes that she will be on the hit list. 'Chimera' sees DS9 joined by another shapeshifter - one of the hundred Changelings sent into space hundreds of years previously. Odo persuades him not to join the Founders, but the new arrival is soon wreaking destruction of his own. In 'Inter Arma Enim Silent Leges', Bashir is coerced by agent Sloan into travelling to Romulus, where he monitors the activities of the Secret Police head. He soon becomes involved in a plot to assassinate an important politician. 'Badda-Bing, Badda-Bang' sees the DS9 involved in a holodeck scenario whereby they must steal one million dollars in order to save Vic Fontaine from Mafia boss Frankie Eyes. In 'Penumbra', Worf is believed lost in battle, but his former wife Ezri Dax takes a shuttle and goes in search of him, reliving her amorous feelings for the Klingon. ''Til Death Do Us Part' sees Worf and Dax experiencing a new attraction while being held for torture by Breen, while Sisko and Kasidy's wedding plans are shaken by a warning from the Prophets. In 'Strange Bedfellows', Worf and Ezri find themselves accused of war crimes in a Cardassian court, while a disguised Guld Dukat plots the downfall of the Emissary with Lai Winn. 'The Changing Face of Evil' sees the Federation joining forces with the Cardassian underground in order to outclass the Breen. In 'When It Rains...', Kai Winn and Gul Dukat plot the demise of the Emissary, while the Federation finds a new ally in the wake of the alliance between the Dominion and the Breen. 'Tacking into the Wind' sees Kira attempting to steal a Breen weapon in order to discover why it is not effective against Klingon ships. In 'Extreme Measures', Bashir and O'Brien attempt to force Section 31 agent Sloan to provide a cure for Odo's terminal illness. 'The Dogs of War' sees Quark shocked to learn that he is to be named Grand Nagus, while the war on Cardassia is affected by the announcement that Damai has returned from the dead to lead his people. Closing the seventh season, in 'What You Leave Behind Part 1', the crew of the Defiant prepare to do battle with the Dominion, while Kira faces execution at the hands of the Jem Hadar. Finally, 'What You Leave Behind Part 2' sees the DS9 personnel preparing to disband in the wake of the Dominion War, but not before the Emissaries of the Prophets and the Pah Wraiths face off one final time.