Star Trek: Deep Space Nine (DS9) focuses on the 24th century adventures of Captain Benjamin Sisko on space station Deep Space 9, an outpost situated near the mouth of a stable wormhole on the far reaches of explored space. Although Sisko commands Deep Space 9, the station actually belongs to the inhabitants of nearby Bajor, who requested Starfleet's protective presence after Bajoran freedom fighters put an end to the brutal Cardassian occupation of their world. Approximately a sixth of the station's 300 permanent residents are Starfleet personnel; there is also a sizable Bajoran militia presence. The rest of Deep Space 9's inhabitants are civilians, most of whom work in the station's Promenade, a kind of indoor marketplace. Initially, Sisko's mandate from Starfleet was to protect Bajor and the station from any hostiles who ventured into the area. But with the discovery of the nearby wormhole—a shortcut through space that leads directly to the uncharted Gamma quadrant—Sisko's mandate has expanded exponentially, as the region becomes the gateway to all manner of visitors, both friendly and extremely hostile.
In 2369, Cardassian forces finally withdraw from 70 years of Bajoran occupation -- on the edge of explored space, a new crew takes command of a former Cardassian space station and makes an incredible discovery that will change the galaxy.
In 2369, Cardassian forces finally withdraw from 70 years of Bajoran occupation -- on the edge of explored space, a new crew takes command of a former Cardassian space station and makes an incredible discovery that will change the galaxy.
A Bajoran terrorist tests Major Kira's loyalties to the Federation when he attempts to rid Bajor of the Federation for good.
Odo, the station's mysterious, gruff and yet incredibly fair shape-shifter Constable, falls under suspicion for a Bajoran's baffling murder -- and xenophobic hatred rears its ugly head in the station's rush to judgment.
During refurbishment, Miles O'Brien unknowingly triggers a formerly dormant Bajoran underground booby trap that releases a potentially fatal virus throughout the station.
As visitors from the Gamma Quadrant start to arrive through the wormhole, Chief O'Brien befriends an unusual alien, Tosk, as hunters descend on the station searching for their humanoid prey
Q arrives on DS9 fresh from exploring the Gamma Quadrant with archaeologist Vash. Soon afterwards, unexplained power fluctuations begin to plague the station, threatening to destroy it.
New evidence reopens a thirty-year-old murder case and Jadzia Dax's previous host, Curzon, is the prime suspect.
An alien criminal, attempting to prolong his life, hides his consciousness inside the mind of a station crew member.
After being swindled by Quark, the Wadi, a visiting delegation from the Gamma Quadrant turns four crew members into 'pieces' for a bizarre game.
Grand Nagus Zek, the leader of the Ferengi Alliance, pays a surprise visit to lowly Quark's Bar to host a conference on exploiting the Gamma Quadrant -- and names Quark, not his own son, as his successor.
A fugitive from the Gamma Quadrant attempts to trade evidence about Odo's people for freedom.
A glimpse of the wormhole and Gamma Quadrant turns tragic, when a runabout carrying Kai Opaka, Sisko, Bashir, and Kira crashes on a planet of eternal war, where it is impossible for the combatants to die.
Chief O'Brien is appointed spiritual leader of a Bajoran village. Meanwhile, Nog and Jake try to help their new friend settle a struggle between two Bajoran villages.
While overseeing an evacuation mission, Kira must try to persuade a stubborn old farmer to leave his home. Back on the station, Jake and Nog set out to turn an inordinate amount of seemingly worthless condiments into profit.
DS9 residents suddenly find their imaginations are manifested in physical form, and a spatial rift threatens to destroy the Bajoran system.
A visiting Lwaxana Troi becomes enamoured with Odo after he retrieves a stolen item of hers from a thief. Meanwhile, an alien computer program wreaks havoc with the station's systems.
Acting out roles both melodramatic and deadly, the DS9 command staff are infected by a viral historical incident archive from an alien culture within the Gamma Quadrant.
After a Cardassian man arrives on the station suffering from an illness that he could only have contracted at a Bajoran labor camp during the Occupation, Major Kira leads an investigation to determine whether he is actually a notorious war criminal.
Orthodox Bajorans voice objections to secular teachings about the wormhole in the station's school, causing violent tensions to erupt between DS9's crew and an increasingly popular fundamentalist faction of the Bajoran faith.
When Quark presents Major Kira with an earring belonging to a presumed dead Bajoran Resistance legend, she and Chief O'Brien journey to Cardassia IV in an attempt to free him from from a slave-labour colony. Meanwhile, an extremist Bajoran faction known as The Circle continues to agitate tensions on DS9 and Bajor.
When Kira is removed from her post aboard DS9, Vedek Bareil invites her to visit his monastery on Bajor to reflect on her next step. Meanwhile, Odo, Sisko, and Li Nalas attempt to discover who is the driving force behind The Circle when they begin arming themselves with weapons from a mysterious source.
After their violent confrontation with the Jem'Hadar, Sisko takes an untested Starfleet ship, the Defiant, into the Gamma Quadrant in an attempt to make peaceful contact with the Founders of the Dominion.
On his newly discovered homeworld, Odo learns to connect with his fellow Changelings. Back on DS9, Sisko grows concerned that the price the Federation is willing to pay for peace with the Dominion may be too high.
When a Klingon fleet under General Martok arrives at the station ostensibly to protect the Alpha Quadrant from the Dominion, Sisko recruits Lieutenant Commander Worf to investigate the Klingons' true intentions.
Believing that the recent Cardasssian coup was orchestrated by the Dominion, the Klingon decision to attack Cardassia puts the Federation-Klingon alliance in jeopardy, and forces Worf to choose between his people and his oath to the Federation.
As the war between the Federation and the Klingon Empire intensifies, Sisko leads an undercover team deep into Klingon territory in an attempt to expose the Changeling impersonating Chancellor Gowron.
While conducting a mineral survey of an uninhabited planet in the Gamma Quadrant, the crew of the Defiant encounter a crashed Jem'Hadar ship and must fight to get it, and themselves, back to the Federation.
With the Dominion in control of DS9 and on track to winning the war against the Federation, Sisko and his crew take a captured Jem'Hadar ship into enemy territory with a mission to destroy the Jem'Hadar's supply of ketracel-white in the Alpha Quadrant.
Sisko's crew crash land their commandeered Jem'Hadar ship on a barren world after being shot down by the Dominion and must fight for survival against a group of Jem'Hadar who have also crash landed. On DS9, Kira struggles to work alongside the Dominion and Jake continues his reporting for the Federation News Service.
Having returned to Earth, Sisko waits for guidance from the Prophets to instruct him on what to do next. Back on DS9, the newly promoted Colonel Kira faces the challenges and burdens of command, and Worf struggles to deal with the loss of Jadzia.
Sisko is joined by an old friend as he searches for the mysterious Orb of the Emissary, but the Pah-wraiths send a vision to distract him. On DS9, Kira mounts a blockade around a Bajoran moon after discovering the Romulans have armed their hospital there. Aboard the Rotarran, Worf leads a mission to destroy a Dominion shipyard in order to honor Jadzia.
Complete episode guide for Star Trek: Deep Space Nine with detailed information about every season and episode including air dates, summaries, ratings, and streaming availability in United States.
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As Federation citizens are evacuated from DS9, Sisko and a skeleton crew attempt to prevent The Circle and the Bajoran military forces under their control from occupying the station. Kira and Dax attempt to reach the Chamber of Ministers on Bajor with evidence of Cardassian involvement in the conflict.
When a violent plasma storm leads to the evacuation of the station, the remaining crew are overtaken by a group of mercenaries led by a timid Trill named Verad who has plans for Lieutenant Dax.
Political tensions rise on DS9 when Bajorans board the station with a orphaned Cardassian whom they have adopted.
Ensign Melora Pazlar, a new arrival on DS9 with a special gravity-based disability, finds an admirer in Bashir. Meanwhile, Quark receives a death threat from one of his former associates.
Grand Nagus Zek assigns Quark to initiate negotiations with a planet in the Gamma Quadrant, the Nagus believes it will help the Ferengi Alliance get a profitable business foothold in new territory. However, the plan is put into jeopardy when Quark's new associate turns out to be more than he appears.
After an attempt on Quark's life, Odo re-opens an unsolved five-year-old murder investigation in which Kira Nerys was originally a suspect.
On the fourth anniversary of his wife's death at the massacre at Wolf 359, Sisko has an unexpected encounter with a mysterious woman visiting the station.
A group of refugees from the Gamma Quadrant travel through the wormhole in search of their fabled homeland, Kentanna.
Quark feels threatened when a charming con artist arrives on the station and opens up a competing bar and casino on the Promenade. Meanwhile, Chief O'Brien is determined to beat Doctor Bashir at racquetball.
Dr. Mora Pol, the Bajoran scientist who studied Odo when he was first discovered, arrives on DS9 with evidence that he has found DNA signatures similar to Odo's on a planet in the Gamma Quadrant.
Chief O'Brien and Dr. Bashir help the T'Lani and the Kelleruns eliminate their stockpiles of deadly biological weapons used in their centuries-long war. However, when both governments decide to make sure no technical knowledge of the weapons remains, O'Brien and Bashir must put their differences aside in the name of survival.
Upon returning from a mission to the Parada system, O'Brien begins to notice the crew acting strange around him and suspects there may be some unknown influence at work.
While surveying nearby star systems for M-Class planets, Sisko and O'Brien find themselves stranded on a previously unknown colony world where the colonists have adapted to life without advanced technology.
After discovering a colony in the Gamma Quadrant, Dax and Odo investigate the mysterious disappearance of several colonists. Back on the station Vedek Bareil visits Kira, and Jake gets a job with Chief O'Brien.
While hosting her first Trill initiate, Dax discovers a tiny, expanding protouniverse that threatens to destroy the entire Bajoran system.
When a damaged Cardassian ship shows up near DS9, Quark is unexpectedly reunited with his lost Cardassian love, who is now a member of the Cardassian dissident movement.
Three legendary Klingon warriors reunite on DS9 seeking Curzon Dax, with whom they entered into a blood oath to one day exact revenge on their sworn enemy. Finding Jadzia to be as worthy a warrior as they felt Curzon to be, they invite her to join them on their crusade.
When a Cardassian freighter, the Bok'Nor, explodes at DS9, the Cardassians blame Federation colonists in the newly established Demilitarized Zone. Meanwhile, Quark is approached by a Vulcan with an unusual business proposition.
Under increasing pressure from Starfleet Command, Sisko tries to rescue Gul Dukat, stop the Maquis from escalating conflict within the Demilitarized Zone, and prevent an all-out war between Cardassia and the Federation.
When an addictive implant in Garak's brain begins to break down, causing the exiled Cardassian extreme pain, Dr. Bashir must convince a reluctant Garak to accept his help.
After suffering an accident whilst traveling through the wormhole, Kira and Dr. Bashir find themselves trapped in the mirror universe first encountered by James T. Kirk a century earlier.
The man most likely to take over as the new Bajoran Kai, Vedek Bareil, is accused of collaborating with the Cardassians during the Occupation.
Chief O'Brien is arrested by the Cardassians for collaborating with the Maquis. However, on Cardassian justice is swift: the verdict is known before the trial even begins, and it's always guilty.
On a camping trip in the Gamma Quadrant to conduct a planetary survey report, Sisko, Jake, Nog, and Quark encounter the ruthless soldiers of the mysterious Dominion, the Jem'Hadar.
When Quark lies about killing a Klingon in his bar, he is pulled into a power struggle between rival Klingon families on Qo'noS and forced to marry the dead man's widow. Meanwhile, Chief O'Brien must confront the fact that Keiko gave up her career to join him on DS9.
When Jadzia begins experiencing violent mood swings and hallucinations, a disturbing secret from Dax's symbiont history reveals a much larger deception.
As she travels to Bajor in search of answers about her past, Kira is abducted by Cardassians, surgically altered, and told she is the missing Obsidian Order deep-cover operative, Iliana Ghemor.
When a Jem'Hadar infant is found in salvaged spaceship wreckage from the Gamma Quadrant, Odo strives to teach the rapidly maturing soldier to think for himself.
Sisko, Jake, and O'Brien accidentally trigger an old Cardassian security system that believes DS9 has been taken over in a Bajoran workers' revolt and puts the entire station in lockdown.
On an exploration mission to the Gamma Quadrant, the Defiant encounters a unique planet that shifts between corporeal and non-corporeal dimensions. Back on DS9, Quark attempts to create a new holosuite program.
When William Riker from the Enterprise unexpectedly arrives on DS9 on vacation, he takes a liking to Kira, who has also been ordered to take some time off. However, when Kira gives Will a tour of the Defiant, it becomes clear that there's more to Will's vacation than meets the eye.
When Ambassador Lwaxana Troi and Keiko O'Brien return to DS9 for the Bajoran Gratitude Festival, residents of the station suddenly become uncontrollably infatuated with one another.
After a transporter malfunction aboard the Defiant, Sisko, Bashir, and Dax find themselves thrown back three hundred years into Earth's dark past without any means of getting home.
With history itself at stake, Sisko assumes the role of a pivotal historical figure in order to restore the timeline, even if it means sacrificing his own life.
After a serious accident aboard a Bajoran shuttle, Dr. Bashir struggles to save Vedek Bareil's life while Kai Winn concludes a peace treaty with Cardassia, putting his ethics to the ultimate test. Jake and Nog reluctantly explore the differences between Human and Ferengi cultures.
Pursuing a Maquis raider to an unstable moon, Kira becomes trapped within an expanding crystal formation that threatens to engulf her. Meanwhile, Nog attempts to persuade a skeptical Commander Sisko to write him a letter of recommendation to join Starfleet Academy.
An ancient Bajoran prophecy complicates the first joint Bajoran, Cardassian, and Federation science mission: an attempt to establish a permanent communications link through the wormhole.
When Grand Nagus Zek revises The Rules of Acquisition to be more philanthropic, Quark and Rom start to question whether their leader has gone insane. Meanwhile, when Dr. Bashir is nominated for a prestigious Federation medical award, his reaction is less than enthusiastic.
After receiving a minor dose of radiation poisoning, Chief O'Brien inexplicably begins experiencing a series of jumps into the future. Meanwhile, a Romulan delegation arrives on DS9 expecting an intelligence report on the Dominion in exchange for the continued use of the cloaking device aboard the Defiant.
After being assaulted by an alien thief in the infirmary, Dr. Bashir wakes to discover he has a dual mystery on his hands: what happened to the station while he was unconscious and why is he suddenly aging so rapidly?
Smiley O'Brien from the mirror universe kidnaps Commander Sisko and convines him to impersonate his deceased, mirror universe self in order to persuade the alternate version of his dead wife, Jennifer Sisko, to join the Terran Rebels.
When a bomb destroys Garak's tailor shop, Odo begins an investigation into who might want the exiled Cardassian killed and why.
When the covertly assembled Romulan-Cardassian attack fleet enters the Gamma Quadrant on a mission of destruction, Garak is forced to interrogate Odo for information on the Founders. Meanwhile, Sisko goes against orders on a mission to rescue Odo.
An invigorated Sisko returns from Bajor and decides to build a replica of an eight hundred-year-old Bajoran lightship, hoping to use it to prove that ancient Bajoran explorers could have made it to Cardassia before developing warp drive.
When Quark's mother breaks Ferengi law by wearing clothes and earning profit, Quark and Rom are forced to return home to Ferenginar in order to convince her to confess and make restitution for her crimes. On DS9, Jake eagerly tries to matchmake his father with freighter captain, Kasidy Yates.
When Kai Winn is appointed Bajoran First Minister, Kira becomes concerned about Winn's growing grip on power. However, when the Kai orders Kira to convince her old Resistance leader to return some farming equipment to the government, the situation rapidly descends into a vicious power struggle.
While Jadzia performs the Trill zhian'tara ritual and meets with the previous Dax hosts, Nog undergoes his stress reaction test in preparation for entrance into Starfleet Academy.
When a destabilizing coup takes places on the Tzenkethi homeworld, a newly promoted Captain Sisko is ordered to take the Defiant on a border patrol to evaluate the situation. However, soon after departing DS9 the Defiant develops a series of malfunctions, leading Sisko to consider that they may have a saboteur onboard.
When an aspiring writer turns up in the middle of the night, an elderly Jake Sisko recounts his life, which has become an endless quest to locate his father, after an accident in the engine room of the Defiant apparently claimed Benjamin Sisko's life.
After crash landing on a planet, Dr. Bashir tries to help members of a rogue Jem'Hadar unit free themselves of their addiction to the drug the Founders use to control them. Meanwhile, Worf tries to adjust to life aboard DS9.
Major Kira and Gul Dukat form an uneasy alliance as they search for a missing Cardassian prison ship, the Ravinok, that disappeared six years earlier while carrying Bajoran prisoners. Back on DS9, Sisko is overwhelmed by the prospect of Kasidy Yates living aboard the station when she decides to take work closer to Bajor.
When Jadzia Dax is reunited with the Kahn symbiont, the wife of one of her previous hosts, together the pair must decide whether or not to defy Trill social taboo and rekindle their former relationship.
When Sisko defends a Karemma ship that has been trading with the Federation without the Dominion's knowledge, a badly damaged Defiant is forced into a dangerous game of cat-and-mouse with two Jem'Hadar ships inside a gas giant.
On a shakedown cruise to Earth to drop off Nog at Starfleet Academy, a malfunction on Quark's new ship causes Quark, Rom, and Nog to crash in the year 1947 in Roswell, New Mexico.
Klingon Dahar Master Kor, Jadzia Dax, and Worf search a remote planet in the Gamma Quadrant for the fabled Sword of Kahless; the mythical, millennia-old weapon of the Klingon Empire's first leader.
A transporter emergency aboard the USS Orinoco replaces the characters in Dr. Bashir's secret agent holosuite program with the physical forms DS9's senior staff.
After the bombing of a Federation conference is revealed to be the work of the Dominion, Sisko and Odo travel to Earth in hopes of uncovering the Changeling responsible.
When Starfleet tightens security measures on Earth and institutes martial law to combat the Changeling threat, Sisko and Odo begin to investigate a suspicious trail of events that imply all may not be what it seems.
Odo is forced to confront his feelings for Kira when Bajoran First Minister Shakaar visits DS9.
Stripped of his former rank, Dukat returns to escort Major Kira to an intelligence sharing conference between Cardassia and Bajor. However, when a Klingon Bird-of-Prey attacks the conference, Kira and Dukat unite to hunt down those responsible.
In an attempt to regain his lost honor, Worf's brother Kurn arrives on the station with a troubling request. Meanwhile, Major Kira and Chief O'Brien investigate Klingon activity near the Bajoran border.
Tired of unfair pay and working conditions, Rom organizes a union for the employees of Quark's Bar and encourages them to go on strike. Meanwhile, Worf has troubling settling into life onboard DS9.
Sisko's role as Emissary is challenged when a 300-year-old Bajoran lightship emerges from the wormhole and the passenger claims that he is the Emissary of the Prophets. Meanwhile, Keiko O'Brien returns to DS9 with some surprising news.
When Worf is accused of destroying a civilian transport ship during an engagement with the Klingons, a hearing is held on DS9 to determine if Worf should be extradited to Qo'noS on charges of murder.
After being convicted of espionage, Chief O'Brien struggles to re-integrate back into his life on DS9 after serving 20 years in an Argrathi virtual prison.
When the counterpart of the long-deceased Jennifer Sisko lures Jake to the mirror universe, Sisko is forced into helping the Terran Rebellian against the Klingon-Cardassian Alliance.
A mysterious woman arrives on DS9 and encourages Jake to begin writing a novel. Lwaxana Troi, pregnant with a son, unexpectedly visits Odo and asks him to help her escape her husband.
Sisko is forced to confront the betrayal of someone he cares about when they are accused of being a Maquis smuggler. As the only two Cardassian residents on DS9, Garak and Ziyal begin spending time together.
After a rogue band of Jem'Hadar attack DS9, the crew of the Defiant reluctantly join forces with a group of loyal Jem'Hadar in order to prevent the rogues from obtaining a dangerous piece of ancient technology.
Dr. Bashir attempts to rid a planet of a bio-engineered plague that was sent by the Dominion as punishment for resistance.
After learning that he is dying from a rare Ferengi disease, Quark decides to auction his vacuum-desiccated body on the Ferengi Futures Exchange. When an injured Keiko O'Brien returns from an expedition to the Gamma Quadrant, Dr. Bashir must take extreme measures to save the life of her unborn child.
When Odo is plagued by an unknown illness that renders him barely able to hold his shape, Dr. Bashir and Odo see not other option but to track down the Founders. Meanwhile, tensions between the Federation and the Klingon Empire continue to rise.
When Grilka, Quark's ex-wife, unexpectedly visits DS9, Quark asks an already smitten Worf to help him pursue his former wife. Elsewhere, O'Brien and Kira struggle with their feelings for each other now that Kira is carrying the O'Brien's unborn child.
On their way back from a medical conference, Jake and Dr. Bashir are diverted to the Federation colony on Ajilon Prime who have been attacked by the Klingons. However, when the the Klingons renew their attacks on the colony, Jake is forced to confront the hard realities of war as battle erupts around him.
Keiko O'Brien returns from the Fire Caves on Bajor possessed by an alien entity which demands that Chief O'Brien follow its every instruction if he doesn't want his wife to die.
When Temporal Investigations arrives on DS9, Sisko recounts how he and the crew of the Defiant traveled back in time to prevent the assassination of Captain James T. Kirk during the original Enterprise's mission to Space Station K-7.
After agreeing to vacation on Risa with Jadzia, Worf is irritated to discover they will be joined by Dr. Bashir, Leeta, and Quark. However, everyone's vacation is thrown into disarray by the arrival of a radical fundamentalist group determined to start a political revolution on Risa.
Sisko, Dax, Odo, and Garak find themselves trapped seven years in the past on Terok Nor, but everyone thinks that they're condemned Bajorans. With Cardassians in control of the station, Odo's memory of a crime he once investigated may be the only key to their survival.
Quark and Odo are forced to put their grievances aside when they crash land on an inhospitable planet and must work together to survive. Back on DS9, Nog returns from Starfleet Academy and moves into new quarters with Jake.
On the eve of Bajor's entry into the Federation, Sisko begins experiencing visions that lead him to ruins of the lost Bajoran city of B'hala. However, when the visions that are guiding him become potentially fatal, Sisko must choose between his faith in the Prophets or his life.
Major Kira is forced to confront her actions during the Cardassian Occupation when a mysterious assassin begins killing members of her former resistance cell.
The discovery of an infant Changeling gives Odo a chance to correct what he sees as the invasive mistakes in his upbringing. Meanwhile, Kira goes into labor with the O'Briens' baby.
Sisko obsessively pursues the former Starfleet officer Michael Eddington, now the leader of the Maquis.
Garak and Worf investigate a coded message which suggests that Garak's mentor, Enabran Tain, is still alive in the Gamma Quadrant. However, when their search for answers leads them into Dominion space, the pair discover something far worse than they had expected.
The crew of DS9 prepares to defend the Alpha Quadrant from an invading Dominion fleet. Still trapped in the Gamma Quadrant, Worf, Garak, and the other prisoners continue their attempts to escape from the Dominion Internment Camp.
Dr. Lewis Zimmerman arrives on DS9 intending to use Dr. Julian Bashir as the model for his new Long-term Medical Hologram, but when Zimmerman's plans threaten to unveil a dark secret that Bashir has carried since childhood, Julian is forced to make a life-altering confession.
Odo falls for a mysterious woman who has been targeted for murder by the Orion Syndicate.
Quark must wrestle with his conscience when his cousin Gaila offers him a lucrative job as a weapons dealer.
Takeny Ghemor, who considers Kira to be his daughter, arrives on DS9 and confesses that is dying. Ghemor wishes to commence the Shri-tal with Kira, a Cardassian ritual in which a dying person reveals their closest secrets to the rest of the family. But the experience dredges up Kira's memories of her own father, who suffered a fatal injury during the Occupation of Bajor.
Feeling depressed, Quark returns home to Ferenginar to visit his mother, but doesn't know whether to be panicked or overjoyed when he learns that she is now the secret lover of the Grand Nagus.
Dax and Worf accompany Martok on his first command since being held by the Dominion. But the ship they are given hasn't seen victory in months and the crew is near mutinous, forcing Worf to decide between loyalty to his commander and loyalty to his crew.
Investigating an isolated planet surrounded by a powerful energy field, the crew of the Defiant discovers the unexpected history of the planet's colonists.
Driven to desperation by the Dominion, the Maquis launch a massive strike against Cardassia. In order to prevent mass Cardassian casualities, Sisko is forced to trust the traitor Michael Eddington to try to stop the missiles from reaching their target.
While salvaging components from DS9's sister station, Empok Nor, the crew run afoul of a disturbing surprise left behind by the Cardassians.
Jake and Nog go through hell and high water while trying to cheer up the war-fatigued Captain Sisko by acquiring a mint-condition 1951 Willie Mays baseball card. Meanwhile, Weyoun arrives on DS9 to meet with Kai Winn and offers to sign a nonaggression pact with Bajor.
With continuing convoys of Jem'Hadar arriving in the Alpha Quadrant, Sisko decides to mine the wormhole to prevent further troop movement. However, this decision forces the Federation into a direct confrontation with the Dominion, and Gul Dukat responds by launching a massive assault fleet against DS9.
Alexander Rozhenko joins the crew of the Rotarran, much to the disappointment of Worf. On DS9, Tora Ziyal returns to the station where Gul Dukat intends to use her to get closer to Kira.
Kira's resistance cell continues to cause trouble onboard DS9, deliberately inflaming tensions between the Jem'Hadar and the Cardassians. But their plots are complicated when the Female Changeling arrives on DS9 to pay Odo a visit. Meanwhile, Sisko relinquishes command of the Defiant to Dax after accepting a promotion.
Tired of being on the losing end of the war, Captain Sisko convinces Starfleet Command to launch a fleet of starships to retake DS9. Meanwhile, time is running out for Rom, who faces execution as an enemy of the Dominion state.
Commanded by Captain Sisko, the Federation fleet begins it's mission to retake DS9 before the Dominion can bring down the wormhole minefield. On the station, Kira's resistance cell desperately try to sabotage the main computer, and Quark seeks out an unexpected ally to help save Rom.
Spontaneously deciding to wed within the week on DS9, Worf and Jadzia go through their own Klingon rituals: Worf on a four day bachelor party with the male members of the crew, while Jadzia deals with her prospective mother-in-law, who deeply opposes the idea of "an alien" marrying into her Klingon household.
The mirror universe version of Kira's long dead love, Bareil Antos, beams aboard DS9 seeking refuge from the Klingon-Cardassian Alliance.
Dr. Bashir works with an eccentric group of genetically engineered humans in the hopes they can become productive members of the Federation. Meanwhile, the Dominion arrives on DS9 offering to negotiate a truce with the Federation.
When Quark and Rom's mother Ishka is captured by the Dominion, Quark leads a team of Ferengi on a mission to Empok Nor to rescue her.
Following the destruction of the starship Honshu, Sisko finds himself stranded on a deserted planet with Dukat, who has become increasingly unstable since the death of Ziyal.
Morn dies unexpectedly, bequeathing his entire estate to Quark, but some of Morn's old acquaintances arrive on DS9 demanding a piece of the action.
After a friend's ship is destroyed by the Dominion, a despondent Sisko contemplates resigning from Starfleet while experiencing visions of himself and his crew as sci-fi writers in 1950s America.
O'Brien, Dax, Dr. Bashir, and their runabout are reduced in size while investigating an anomaly. However, when the Jem'Hadar attack and commandeer the Defiant, the trio are left with no choice but to take their miniature runabout inside the Defiant to help Sisko and the others retake the ship.
O'Brien, working undercover for Starfleet Intelligence, infiltrates the Orion Syndicate, the Alpha Quadrant's main organized crime ring and befriends the man he will have to betray.
On a mission to recover a Federation informant from the Dominion world of Soukara, Dax is injured and Worf must choose between completing the mission or saving his wife. on DS9, O'Brien enlists Bashir's help to defeat Quark in a game of tongo.
After receiving some disturbing information from Gul Dukat, Kira uses the Orb of Time to travel into the past to discover the truth about what happened to her mother during the Occupation of Bajor.
Dr. Bashir's plans to attend a medical conference on Casperia Prime are canceled when the Department of Internal Affairs arrives on DS9 and announces there has been a major security breach and a member of the senior staff has been passing information to the Dominion.
With mounting losses in the Federation-Dominion war, and the looming specter of defeat, Captain Sisko enlists Garak's help to bring the Romulan Empire into the war. However, Sisko may have to sell his soul and the values Starfleet stands for in order to achieve his mission.
Odo consults Vic Fontaine, a self-aware holographic lounge singer, about his romantic relationship with Kira.
The discovery of a 30,000 year old Bajoran tablet buried under the holy city of B'hala claiming the time of the Reckoning is at hand, and that the future of Bajor will be decided by its outcome.
On their way to Ferenginar, Jake and Nog's runabout comes under attack from the Jem'Hadar, and they are rescued by the Valiant, a ship manned by an elite group of over-eager Starfleet cadets who have bitten off more than they can chew.
When Grand Nagus Zek is deposed by the Ferengi Commerce Authority for granting Ferengi females the right to wear clothes with an amendment to the Ferengi Bill of Opportunities, Quark is forced to assume a female identity to prevent Brunt from becoming the next Grand Nagus.
When an accident on the planet Golana sends Molly O'Brien through a mysterious vortex three hundred years into the past, she returns to the present eighteen years old with no immediate recollection of her previous life or her family.
After receiving a distress call, the crew of the Defiant race to save a Starfleet captain stranded on an inhospitable planet. Back on DS9, Jake follows Quark's latest scheme for story research.
Sisko is chosen to lead an invasion into Cardassian territory, ignoring a warning of impending doom if he leaves DS9 from the Prophets, resulting in fatal consequences for a member of the crew.
Ezri Dax struggles to cope with the memories of her previous hosts while attempting to forge new relationships with Jadzia's old friends. Meanwhile, Garak tries to manage a severe bout of claustrophobia.
Captain Solok, a Vulcan and former classmate of Captain Sisko, challenges Sisko and the crew of DS9 to a game of baseball.
The genetically-engineered humans who had previously visited DS9 return to the station asking Dr. Bashir to help rouse Sarina from her cataleptic state.
A Vorta offers Odo valuable information on the Dominion in exchange for asylum. Back on DS9, O'Brien and Nog sail down the Great Material Continuum.
With the Dominion War raging, the aging Klingon warrior Kor feels left out of the action, and requests an opportunity to die with honor as a warrior. However, Kor's efforts are stymied by Martok, who holds a deeply personal grudge against Kor.
During a supply run to the isolated outpost AR-558, Sisko and his away team volunteer to stay with the besieged and demoralized unit, which is about to come under attack by a much larger contingent of Jem'Hadar soldiers.
Kira is abducted and taken to Empok Nor by the Cult of the Pah-wraiths and discovers that the group is now led by "the Master" - Gul Dukat.
Severely depressed over the loss of his leg at the Siege of AR-558, Nog struggles to return to normal life aboard DS9 and seeks shelter within the holographic world of Vic Fontaine.
Ezri returns to her family home on New Sydney to seek assistance in locating Chief O'Brien, who has disappeared while searching for the widow of a dead friend.
When Grand Nagus Zek is kidnapped by the Klingon-Cardassian Alliance while on a business trip to the mirror universe, Quark and Rom have three days to secure a cloaking device for the Alliance or Zek will die.
After several crew members are murdered, Ezri reluctantly summons the residual consciousness and personality of her symbiont's past, the psychopathic Joran Dax, to help her catch the killer.
Odo meets another of the Hundred, infant Changelings who were sent out by the Founders hundreds of years ago to explore the galaxy.
When holographic mobsters assume control of Vic Fontaine's lounge, the DS9 residents plot to run Vic's rival out of business and restore the program to normal.
Attending a medical conference on Romulus, Dr. Bashir is contacted by Sloane and finds himself embroiled in an elaborate scheme devised by Section 31.
When Worf remains missing after a battle with the Dominion, Ezri takes a shuttle against orders to search for him. On DS9, Sisko makes plans for his future with Kasidy.
On DS9, Sisko agonizes over his vision from the Prophets, warning him not to marry Kasidy, and Kai Winn receives a vision foretelling the arrival of a guide who will help her restore Bajor. Meanwhile, Ezri and Worf are interrogated aboard a Breen ship and unexpectedly witness a disturbing turn of events, one which may change the course of the entire war.
On DS9, Dukat continues his manipulation of Kai Winn, and Kasidy finds it difficult being married to the Emissary. Now aboard a Dominion vessel, Worf and Ezri continue to plot their escape from captivity, and in the wake of the new Breen-Dominion Alliance, Damar makes a shocking decision.
The Breen-Dominion Alliance launches a devasting attack at the heart of the Federation, and the Federation Alliance struggles to maintain its foothold in Cardassian space. Kai Winn, under the guidance of Dukat, begins researching forbidden texts about the Pah-wraiths. On Cardassia, Damar begins a rebellion against the Dominion.
Kira, Odo, and Garak travel behind enemy lines to aid Damar's rebellion against the Dominion. On DS9, Dr. Bashir discovers something disastrous during his research, and Chancellor Gowron arrives on the station with an agenda of his own.
With the help of Kira, Odo, and Garak, the Cardassian Rebellion plots to steal a Breen weapon for the Federation. On DS9, Dr. Bashir and Chief O'Brien continue to try and find a cure for Odo, and Gowron's reckless attacks against the Dominion prompt Worf to take drastic action.
In a desperate attempt to locate a cure for Odo, Dr. Bashir and Chief O'Brien lure a member of Section 31 to DS9.
Trapped on Cardassia Prime after an ambush, Kira, Damar, and Garak plot to turn their rebellion into a revolution. On DS9, Grand Nagus Zek visits the station with surprising news about the future of the Ferengi Alliance.
The Federation Alliance begins its final assault on the Dominion. On Cardassia Prime, Kira, Damar, and Garak begin recruiting ordinary citizens to their revolution. Meanwhile, Gul Dukat and Kai Winn continue their plan to release the Pah-wraiths from the Fire Caves on Bajor.
In response to the Dominion destruction of Cardassian cities, the Cardassian military switches sides. Damar, Kira, and Garak launch an assault on Dominion Headquarters. The Federation Alliance makes a final push for victory. Sisko's role as the Emissary of the Prophets reaches its conclusion.