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Memory Beta, non-canon Star Trek Wiki
WARNING! This article contains MAJOR spoilers for the recently released novel Moments Asunder. Caution is advised.
For the mirror universe counterpart, see Ezri Dax (mirror).

Ezri Dax is a joined female Trill, born as Ezri Tigan on the world of New Sydney in the year 2354. Ezri started her Starfleet career as an assistant counselor aboard the USS Destiny, up until she was joined with Dax. Ezri was later assigned to Deep Space 9, the original USS Defiant and its successor. During the Borg Invasion of 2381, Ezri was promoted to captain, having switched to command after the Dominion War, and took command of the USS Aventine. states that Ezri was born on Trill. However, this contradicts an on-screen personnel file and episodic continuity.


Early life

Ezri's mother, Yanas Tigan, was the owner of a very successful mining concern on the world of New Sydney. Ezri and her mother, who wanted Ezri to help run the family business, argued constantly.

Ezri refused to let her mother control her the way she did her two brothers and refused to join the family business. Instead, she enrolled in Starfleet Academy and studied to become a counselor. (DS9 episode: "Prodigal Daughter")

Joining with Dax

Ezri attended Starfleet Academy Medical School from 2372 to 2374, focusing on psychology. Her final year of training was waived. (ST website:

In late 2374, Ezri held the rank of ensign and served as assistant counselor aboard the starship USS Destiny. In that year, the Destiny was diverted because of a medical emergency and traveled to Deep Space 9. Upon arrival, the Destiny docked with a runabout that contained the Trill symbiont, Dax, who had been separated from its previous host, Jadzia. Jadzia Dax had been brutally murdered by Cardassian Gul Skrain Dukat, with the assistance of a Pah-wraith. The Dax symbiont was escorted by DS9's chief of security, the Changeling, Odo. Dax needed to a new host in a matter of weeks or it wouldn't survive. When a shape-shifting Founder of the Dominion impersonated Ezri's lover, Ensign Brinner Finok, and attempted to kidnap the Dax symbiont, Ezri was the first to realize that something was wrong. Soon after the foiling of the kidnapping and the capture of the Changeling, the ship was attacked by Jem'Hadar vessels. Dax's condition worsened, and needed to be joined immediately. Ezri had never wanted to be joined, but as Brinner Finok was still missing, Ezri was the only available Trill to join Dax with. Ezri agreed to undergo the joining procedure, and became the ninth host of the Dax symbiont, Ezri Dax. Brinner Finok would later be found safe in a medical supply closet, but their relationship did not continue after Ezri's joining. (DS9 episode: "Tears of the Prophets"; DS9 - The Lives of Dax short story: "Second Star to the Right...", "... And Straight on 'til Morning")

Deep Space 9


Ezri in 2375

Ezri, confused by all of her new memories, sought out the one constant in her previous two incarnations—Starfleet Captain Benjamin Sisko, on Earth. Dax's host Ezri initially preferred not to be called "Old Man" by her new mentor and longtime friend, Ben Sisko. (DS9 episodes: "Image in the Sand", "Shadows and Symbols", "Afterimage")

Dax returned to DS9 with Sisko where she received the rank of lieutenant junior grade and position of station's counselor. She served in the position through the end of the war. (DS9 episodes: "Image in the Sand", "Shadows and Symbols")

After "returning" to DS9, she began counseling Elim Garak for his claustrophobia. After some time and work, they discovered his attacks were triggered by his guilt for helping the Federation attack Cardassian targets. (DS9 episode: "Afterimage")

Ezri fought in the Siege of AR-558. (DS9 episode: "The Siege of AR-558")

Just prior to the end of the war in 2375, Ezri began a relationship with Dr. Julian Bashir, who may have had unresolved feelings for her previous host, Jadzia. (DS9 episode: "The Dogs of War")


Ezri in 2376.

In January of 2376, Ezri brought the legendary Sword of Kahless into the possession of the new Klingon Chancellor, Martok, on the world of Boreth at a pivotal moment of a Klingon civil war. (DS9 - The Left Hand of Destiny novel: The Left Hand of Destiny, Book Two)

In April of 2376, Dax was onboard the USS Defiant when a surprise attack by the Jem'Hadar killed the ship's new CO, Commander Tiris Jast. Drawing on the memories of Dax's previous hosts, Ezri took command and defeated the attacking Jem'Hadar. The experience made Ezri realize that she was capable of so much more now that she was joined, and made the switch to the Command Track. It also earned her a nomination to receive the Starfleet Citation for Conspicuous Gallantry.

April also saw a strain on Dax's relationship with Bashir when she began to explore the connection with her previous hosts and momentarily took on the personality of Jadzia Dax when they were making love. The incident spooked and offended Bashir who stormed out of Dax's quarters. The pair later reconciled after Bashir nearly died. (DS9 - Avatar novels: Book One, Book Two)

Ezri and Julian traveled to the world of Sindorin to destroy the laboratory of Dr. Ethan Locken, a rogue former agent of Section 31, who was breeding an army of Jem'Hadar Soldiers. (DS9 - Section 31 novel: Abyss)

Ezri was given the position of first officer aboard the USS Defiant for its three-month exploratory mission of the Gamma Quadrant by the mission's commander, Elias Vaughn.

During the Gamma Quadrant mission, Ezri commanded a shuttle mission attempting to protect the Vahni Vahltupali from the debris of their shattered moon (an effort that tragically led to the mission's only casualty, Ensign Gerda Roness), mediated a solution to a caste conflict between the Cheka and Yrythny species, encountered an ancient alien artifact that actually separated her from Dax for a time, and confronted Commander Vaughn when he was letting personal desires get in the way of the mission. (DS9 - Mission Gamma novels: Twilight, This Gray Spirit, Cathedral, Lesser Evil)

Upon her return to the Alpha Quadrant, Ezri found herself in the middle of the Bajoran Parasite crisis. The alien Parasites had a genetic link to the Trill symbionts and had been encountered by a previous Dax host, Audrid. (DS9 novel: Unity)

The revelations about the origins of the Parasites brought major civil unrest to the world of Trill when Ezri returned there to testify about the Parasite affair. After a radical faction killed a large percentage of the symbiont population, the Trill President, Lirisse Maz, ordered a moratorium on joining, allowing the symbionts to replenish their population.

Ezri and Julian ended their relationship soon after, when Ezri began to believe that his feelings for her were a by-product of his unrequited feelings for Jadzia. (DS9 - Worlds of Deep Space Nine novella: Trill: Unjoined)

After these events, Dax was made second officer of Deep Space 9 and to have a permanent station in Ops, Captain Kira and Commander Vaughn assigned her to man the communication station during the alpha-shift. (DS9 novel: Ascendance)


After serving a year as second officer, she decided to widen her skill set and attended Starfleet's Advanced Tactical Training on Tellar. When she returned to the station, Dax started to work the beta-shifts at the tactical station on top of her comm duties to fill in for tactical officer Sam Bowers who was regularly assigned to the Defiant for patrol duty.

In the following months, Dax faithfully did her duties during one crisis after the next, dealing with Iliana Ghemor, Taran'atar and the Ascendant. Through these events, her confidence and ambition grew to test herself and get ahead in Starfleet. She wished to define her own identity and not just live in the shadows of Dax's former hosts. She eventually concluded that serving on Deep Space 9 was more to do with Jadzia's life than with her own and started to consider requesting a shipboard assignment. (DS9 novels: Warpath, Fearful Symmetry, The Soul Key, Sacraments of Fire, Ascendance)

The Aventine


By 2380, Ezri was promoted to lieutenant commander and was transferred to the USS Aventine, assigned to the duties of second officer. (TNG novel: Greater Than the Sum)


After the ship's captain and executive officer were killed while defending the Acamar System from the Borg, Ezri assumed command of the USS Aventine as the highest ranking surviving officer. A week later, Starfleet Command field-promoted Ezri to the rank of captain, granting her permanent command. Ezri convinced Starfleet that the wreckage of the Columbia, discovered eight years previously by Jadzia Dax, could hold the key to understanding the Borg's new ability to travel vast distances without being detected, and the Aventine was assigned to a salvage mission. The mission was cut short after Admiral Jellico reassigned the Aventine to the fleet defending Trill against further Borg attacks. However, the Caeliar Arithon hid in the Columbia wreckage to board the ship, stole the runabout USS Seine, and opened a subspace tunnel, hoping to find his former planet Erigol, and merely found the supernova remnant now the Azure Nebula. (ST - Destiny novel: Gods of Night)

This placed the Aventine in position to answer the USS Enterprise-E's distress call and assist them in defeating a Borg cube. Captain Jean-Luc Picard ordered the two crews to investigate the tunnels to find ways to mine the nebula and collapse them to prevent further Borg incursions, despite protests by Dax and several of the Enterprise senior staff who considered the tunnels to be too valuable as an exploratory tool. Ezri initially felt awkward around the Enterprise, and in particular Worf, whom she had not seen since her promotion. She also began to doubt her abilities to command a starship. Her first officer, Sam Bowers, convinced her to speak to Worf, and the two reconciled, with Worf indicating that her continued success did honor to Jadzia's memories.

Scientific analysis performed by Dina Elfiki and Gruhn Helkara determined that attempts to collapse the subspace tunnels could cause catastrophic reverberations, and the dynamics of the supernova remnant proved to thwart any attempts to create a minefield. After consulting with Admiral Nechayev and requesting reinforcements, Picard ceased production of the self-replicating mines Dax had suggested and instead had the ships focus on opening the tunnels, hoping to locate the staging area of the Borg, with the Aventine entering the first tunnels able to be opened. After the arrival of an allied fleet of several hundred ships, the Enterprise and Aventine traversed one of the tunnels together, and ended up near the Carina Arm near the median between the Delta and Gamma Quadrants, where they fought and were boarded by Hirogen hunters. When the two vessels returned to the nebula, they found a graveyard of ships from an invading force of seven thousand Borg cubes. Captain Dax, certain that the advanced weaponry of the Aventine could be of use in saving something from the Collective, set course for Earth, forcing the Enterprise to chase after. (ST - Destiny novel: Mere Mortals)

Picard manages to convince Ezri to stand down and contact Starfleet for new orders. Unfortunately, Starfleet has no new orders for them, and instead gives them authorization to do whatever it takes to stop the Borg. Shortly afterward, the Titan under the command of Captain Riker appears, with Captain Erika Hernandez—long considered dead after the Columbia vanished 200 years earlier.

Dax and Hernandez worked together to devise a plan to stop the Borg by using Hernandez—now infused with Caeliar Catoms—to impersonate the Borg Queen by accessing a Borg Vinculum. Despite Picard's disapproval of the plan, Dax and Hernandez proceed anyway. Worf attempts to convince Ezri to call off the attack, but is unsuccessful.

Hernandez located a lone Borg scout ship to attack and the Aventine ambushed, disabled and boarded the Borg vessel. Ezri's plan was successful, and Hernandez accesses the ship's Viniculum, using her Catoms to impersonate the Queen. Under Hernandez's influence, the Borg turn on themselves, and half the invasion force is destroyed. However, the real Queen quickly reasserts control over the Collective and takes personal control over the scout ship. The Aventine is attacked by the reawakened scout ship, but manages to beam its strike teams back aboard. An explosive device inside the Borg scout ship is then detonated, destroying the vessel.

After the mission, Hernandez informs Ezri of a startling revelation: The Borg are the product of a botched fusion between Caeliar and humans from the Columbia who were thrown back in time in the cataclysm that destroyed the Caeliar's homeworld two hundred years prior. Ezri and Hernandez then come up with another plan to enlist the Caeliar's aid in dismantling the Collective. Although Picard initially disapproves of this plan, Riker is able to convince him otherwise.

Ezri is present on the bridge of the Enterprise to witness the end of the Borg invasion, and of the Borg Collective itself at the hands of the Caeliar. (ST - Destiny novel: Lost Souls)


Ezri Dax in 2382

Shortly after the creation of the Typhon Pact, the Aventine was sent to assist Julian Bashir into Breen space. The meeting between Captain Dax and Doctor Bashir did not go well, as their relationship was still highly strained. (ST - Typhon Pact novel: Zero Sum Game)


In 2383, Starfleet sent the Aventine to the Venetan Outpost V-4 to investigate Tzenkethi activity there. While on this mission, Ezri was reunited with an old classmate, Commander Peter Alden who was attached to Starfleet Intelligence. During the mission, Commander Alden's behavior became erratic and Ezri relieved him of duty. Ezri was overridden in this decision by Admiral Leonard James Akaar. Subsequently, it was revealed that Commander Alden's behavior was a ruse to allow him to more freely investigate Tzenkethi movements. (ST - Typhon Pact novel: Brinkmanship)


After Julian Bashir resigned from Starfleet and attempted to provide a cure to the Andorians for their reproductive crisis, President Pro-Tempore Ishan Anjar ordered Dax to stop Bashir by any means necessary. The Aventine was later involved in a standoff at the Andorian border with two ships. Dax attempted to extradite Bashir from the freighter he was hiding on but the Aventine took damage due to a concealed weapon system.

Later after Bashir was returned to the Aventine, Dax, along with Simon Tarses and Sam Bowers assisted in getting Bashir to Andor, in defiance of the Federation President, the USS Warspite, and USS Falchion. After the cure was disseminated, she surrendered to her security officer, along with Bashir. (ST - The Fall novel: A Ceremony of Losses)

After the Andor incident, Dax was imprisoned at the Jaros II stockade. She was visited by Christine Vale who had temporally taken command of the Lionheart and wanted to hear her side of the story. She then implored Vale to find Julian and set him free no matter the cost. While Vale promised that Rear Admiral Riker would ensure that Dax would have her day in court, Dax was not confident that would be the case. Dax felt that she, Julian, and the others had done the right thing and it was now time to pay the price. (ST - The Fall novel: The Poisoned Chalice)

Later in 2385 it was revealed that Ishan Anjar was long dead. Baras Rodirya - the man who had taken his identity during the Cardassian Occupation of Bajor - was revealed to be working with the Cardassian group the True Way. Baras was personally arrested by Attorney General Phillipa Louvois and removed from office. Admiral Akaar was soon authorized by President Pro-Tempore Sipak to drop all the charges against Captain Dax. Dax was issued a commendation for her actions and reinstated as captain of the Aventine. (ST - The Fall novel: Peaceable Kingdoms)

In November 2385, she was in command when Admiral Riker, under the influence of the Cytherians, transferred his flag aboard the Aventine and ultimately took over the ship until the conflict was resolved. (TNG novel: Takedown)


In late 2386, after his defeat of Section 31 and Uraei rendered him catatonic, Dax and her chief medical officer Simon Tarses delivered Julian Bashir to Cardassia Prime, so that their friend would be cared for by the Castellan of Cardassia, Elim Garak. (Section 31 novel: Control)

She was presumably part of the group of friends referenced by Katherine Pulaski, who ensured that when she visited Cardassia afterwards (circa 2387) to collect an award for Bashir, Elizabeth Lense and her own work with the Andorian crisis, Bashir's bear Kukalaka was delivered to him. (DS9 novel: Enigma Tales)

WARNING! This article contains MAJOR spoilers for the recently released novel Moments Asunder. Caution is advised.

Soon afterwards, Ezri was part of a mission that travelled forward in time to fight the Devidians, who were attempting to destroy multiple timelines. During the mission, Dax was exposed to temporal energies that instantly aged her to death. (ST - Coda novel: Moments Asunder)

Alternate versions

During Kira Nerys' vision from the Prophets, Ezri was represented by a woman named Zeir. (DS9 novel: Warpath)

Starfleet service record

location assignment dates rank or rate assignment insignia rank insignia
Starfleet Academy student officer 2372-2373 cadet Assignment badge. Uniform collar rank insignia image.
2373-2374 Uniform collar rank insignia image.
USS Destiny assistant counselor 2374-2375 ensign Uniform collar rank insignia image.
Deep Space 9 counselor 2375-2376 lieutenant junior grade Uniform collar rank insignia image.
USS Defiant II first officer 2376 lieutenant Uniform collar rank insignia image.
Deep Space 9 communications officer / second officer 2376-2377
Advanced Tactical Training trainee officer 2377
Deep Space 9 alpha-shift comm officer / beta-shift tactical officer / second officer 2377 onwards
USS Aventine second officer by 2380-2381 lieutenant commander Uniform collar rank insignia image.
commanding officer 23812387 captain Uniform collar rank insignia image.



Preceded by:
Host of Dax
from 2375
Succeeded by:
unestablished, eventually Dax
Preceded by:
Commanding officer of the USS Aventine
Succeeded by:
hosts of the Dax symbiont
primary universe Lela YuraniEnjana* • Penzak* • Tobin FendusEmony OdarenDax (Ensign)* • AudridToriasJoran BelarCurzon AntraniJadzia IdarisVerad Kalon* • Ezri TiganDax (Enterprise-J captain) Trill emblem. icon image.
alternate timelines Jadzia Dax (alternates)Ezri Dax (alternates)Yedrin
mirror universe Curzon AntraniJadzia IdarisEzri Tigan
USS Destiny personnel
Emblem of the United Federation of Planets Brinner FinokFulghumBilly JamisonJona MeelJohn MacAfeeMarcia MacAfeeRaymerFranklin SolonEzri TiganT'pek Seal of the Federation Starfleet
Starbase Deep Space 9 personnel and residents (original station)
station personnel K. AdabweM. AhzedT. AimatsuAleco V.R. AlfonzoAlle T.AltmanAmranK. AndrewsT. AneN. AponteJ. AsheAylam E.J. S. BashirBattes A.BileckiJ. BlackmerP. BoudreauxS. BowersJ. BroomeCardokCarltonS. CarsonCenn D.J. ChaoJ. ChavezH. CollinsF. CortezCostelloCryanD. CzirakyG. DavisE. DaxJ. DaxDevroS. DouglasM. EddingtonEddonEtana K.Evik N.Gaysd T.Girani S.GoodmanGordimerGreskrendtregkGueretteHageHava R.T. JastJataq'qatS. JonssonKaboKahrimanisKellyKira N.V. KnezoJ. KurlandKurnT. KwiatkowskiS. ch'LarnC. LingP. MatthiasMcCormickMcEwianK. MerimarkMonyodinT. MooreMoruI. MuckerheideMunsonNalan B.J. Si NaranNedani I.Nev R.NguyenNogM.E. O'BrienOccinoOdoD. ParksPertweeH. PetersenPhongsitG. PrimminRedacCh'RellanK. RichterRo L.RomG. RonessSangerSarish M.A. SelznerJ. SenkowskiSetrin Y.R. th'ShantShul T.Shula S.SimakB.L. SiskoZ. SlaineJ. SmithN. SthiliW. StinsonM. StrangStrekC. SwannigTaganaS. TaranS. TarsesA. TaverasDarl TavrosTelnorriP. TenmeiTerekT. ch'ThaneTollandM. TomsonT'PeynTrulliE. Vaughnzh'VeskVu K.Wasa G.Wayeh S.D. WilkensWorfWoros K.YamaguchiD. YarrowYevlin M. Emblem of the United Federation of Planets. Bajoran emblem.
Seal of the Federation Starfleet. DS9 insignia.
station residents AluuraA. WyossL. ArlinAriosBarys K.Betenn B.Betenn C.Betenn K.BokatBrocBroikBylaCadaraCaprilChalan A.Chon S.ChramConpapDalba S.DrakV. FontaineA. FontanaFreylaFroolE. GarakGrimpE. GrofHadronHatram N.HetikJas-qalJhakkaKagaKalawLeetaLondar P.MaikiMalor B.Malor T.MardahMartokMirehMo'NekeMornM'PellaKeiko O'BrienKirayoshi O'BrienMolly O'BrienQuarkRasmus S.RhitSardaS'taassN. SardopolousShul AbaJ. SiskoT'AraTaran'atarJ. TharenTigart H.Tir R.Tora Z.TreirVisshKasidy Yates
Starbase Deep Space 9 personnel and residents (second station)
station personnel Aleco V.AllasarE.g. AnsargJ. BashirB. BecerraV. BixxJ. BlackmerP. BoudreauxJ. CandlewoodCardokCenn D.H. CollinsJ. CollinsB. CrusherA. d'ArnaudV. deGromO. DellasantG. DesjardinsEtana K.S. DouglasHava R.B. HerriotE. JuarezV. KnezoS. ch'LarnP. MatthiasK. MerimarkE. MinnarNogM.E. O'BrienD. PhloxS. RavidK. RichterRo L.N. SaygurShul T.Z. SlaineW. StinsonT'LuneP. TenmeiL. ThorneValinarVerlonR.K. VissP. WalenistaZhang S.
station residents Altek D.AluuraBroikDamas H.FroolGrimpKala M.M'PellaOrcamQuarkShmengeUlu L.Zirk
Defiant personnel
USS Defiant (NCC-1764) T. BarrowsT. BlairS. GarrovickJ. HamiltonK. MbuguaC. NynR. SabapathySerlingT. ShullStevokE. SutherlandT'LehrM. Willoughby UFP emblem image. Starfleet emblem. Assignment patch image.
USS Defiant (NX-74205) (I) AbdabaT. AmarV. AaastaakArla R.J. BashirH. BlakeBremertonS. CarsonE. DaxJ. DaxM. EddingtonH. IlarioJoson W.KellyKira N.KizilbashKolettaMeyerE. MuñizN'Kduk-ThagNogM. O'BrienOdoReeseP. ReeseK. RichterB. SiskoF. StevensR. TannenbaumT'RulC. L. M. D. C. TelTutuT. WeymouthJ. WheelerWorf
USS Defiant (NCC-75633) (II) Aleco V.J. BashirBoehmS. BowersJ. CandlewoodCassiniCelesteJ. ChaoE. DaxG. ForteD. GervasiGordimerQ. HeinsK. HunterT. JastE. JuarezKira N.J. KurlandLankfordM. LeishmanA. McCallumK. MerimarkMinecciM'NokC. MooreL. NeeleyNogM. O'BrienOdoB. PermenterT. RahimK. RichterG. RonessJ. SenkowskiB. SiskoN. SthiliStovP. TenmeiT. ch'ThaneThronT'rbVanBuskirkE. VaughnWorfA. Zucca
mirror universe ISS Defiant (Constitution-class)
Terran Empire
Imperial Starfleet
J. ArcherKelbyT. MayweatherPhloxM. ReedA.G. RobinsonH. SatoT'PolC. Tucker Terran Empire emblem.
Terran Rebellion
Galactic Commonwealth
J. BashirS. BowersE. DaxJ. DaxA. DeCurtisLeetaE. MuñizM. O'BrienPennakB. SiskoStevensP. TenmeiT. ch'Thane Terran emblem.
USS Aventine personnel
Emblem of the United Federation of Planets. AltossS. BowersCh'MarasE. ConstantinoCupelliL. D'OdoricoN. DarrowE. DaxDexarEnglehornL. GlauS. GredenkoG. HelkaraHockneyT. KandelL. KedairN. K. TorC. KomerL'KemM. LeishmanLoskywitzMalayaO. MavroidisO. MirrenG. chim NakNavokP7-RedIlar P.RavosusN. RiordanP. RhysSelidokSimmerithT'PrelM. TakagiS. TarsesTharpTovakYlacamYott Seal of the Federation Starfleet.


  • Ezri Dax was portrayed by Canadian actress Nicole de Boer in Star Trek: Deep Space Nine from 1998-1999. De Boer was pleased with Ezri's promotion to captain, having been given a copy of a novel by David Mack. She commented: "Just the fact she got to captain – I mean, that is pretty cool – and it does make sense for Ezri because she was on that sort of trajectory. She was growing. I would have liked to have had a little longer on the show to become even more confident. What would be cool is if we did another show and you did see me walk through the doors with wonderful confidence because she was so lost before. And they [the other characters] would be like, 'Whoa! That’s Ezri! She’s really grown a lot'. But then we could also see how those people inside her have manifested in interesting ways now that she’s really grasped how to do it. That would be really fun just to explore all that stuff but with more confidence than I could at the time because it was brand-new for her".[1]
  • In the post-finale "season eight" segments of the documentary What We Left Behind, Ezri commands the USS Emmett Till.

Appearances and references



ST - Section 31 novel: Control


External links