[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/picture_113.png]]
[[caption-width-right:350:Body of a Changeling. Mind of a Trill. Fashion sense of [[Series/StarTrekVoyager Neelix]].]]
Nog is piloting a runabout in combat with Cardassians. Suddenly, Jake interrupts him by appearing outside and knocking on the window. This whole thing has been a simulation to help Nog study for his entrance exam into Starfleet Academy. Quark disapproves of Nog's ambitions and tries to rope him and Jake into writing erotic holosuite programs, but Nog reiterates his desire to join Starfleet.

Meanwhile, Dax summons Sisko, O'Brien, Bashir, Kira, Odo, Quark and Leeta together to make a request. She wants to use them for her Trill zhian'tara ritual, which will imprint one of her previous host's memories into each of them so that she can interact with all of her past selves. Everyone but Quark agrees immediately, and even the Ferengi allows himself to be persuaded with a little ear massaging. Dax explains that the host's personality will control their bodies, but they will remain conscious and able to reassert control at any time.

Dax's first host is the diplomat Lela, inhabiting Kira. Jadzia learns that her habit of folding her hands behind her back originates from Lela, who developed the habit after getting mocked for her emphatic hand gestures. Next, she meets Tobin, who bites O'Brien's nails and apologizes as Jadzia compliments his brilliant work. Emony is hosted by Leeta, who enjoys the dabo girl's athletic physique and discusses gymnastics. Audrid extols the values of motherhood but gets interrupted by Quark's complaints. Torias breaks Bashir's diet by scarfing down sweets while recommending that Jadzia enjoy the simple pleasures of life.

It's all been fun, but now it's time to meet Joran, the murderer. Sisko has volunteered for this duty, and Odo places him in a holding cell just to make sure. Joran seems calm at first, asking Jadzia whether she practices music and thinks about him, which she does. But then he starts pressuring Jadzia to let him out of the cell. When she refuses, he starts hammering Sisko's body against the forcefield. Jadzia tells Sisko to reassert control, and suddenly Joran collapses. But when Jadzia lowers the forcefield, Sisko grabs her throat and starts strangling her. Joran is still in control! But Jadzia manages to beat the Joran out of Sisko, who assures the "old man" that he's himself again.

Reflecting with the fully recovered Sisko, Jadzia talks about how she's most afraid of her final host, Curzon. He was the one who denied her application to the Symbiosis Commission, causing her to become the first host to ever successfully reapply. She's felt a lingering sense of inadequacy and even delayed participating in the zhian'tara out of a fear of not measuring up to the other hosts. Sisko gives Jadzia a pep-talk, assures her that she does measure up, and tells her to simply hash it out with Curzon.

Odo takes on the memories of Curzon. Due to the changeling's unique nature, their personalities fuse much like an actual Trill host, and the pair shift into an amalgamation of their appearances. Curzon proves to be a lively and gregarious fellow and announces that both sides of his personality enjoy this experience. He runs off to get reacquainted with Sisko, drink, play pranks on Quark, and gamble. When Dax tries to corner him about why he didn't oppose her reapplication, he brushes her off, saying he probably felt sorry for her. Dax is unsatisfied, but it looks like she'll be seeing a lot more of Curzon because he announces that both he and Odo have decided to stay the way they are.

Meanwhile, Nog flunks his entrance exam, and he can't understand why. Quark sympathetically tells him that he'll always have a place at his bar. A suspicious Rom checks the computer and discovers that Quark tampered with the testing program. He confronts Quark and tells him that he's going to expose the deception to give Nog another chance, and he'll burn down Quark's bar if he ever messes with Nog again.

Dax is upset. Not only has she failed to overcome her inferiority complex, but she's missing Curzon's personality so long as he gallivants about in Odo. She confronts Curzon and stands her ground, ultimately forcing Curzon to concede. He admits that he flunked Jadzia because he was in love with her and was afraid of going too easy on her, but after doing so, he felt ashamed that he had stolen her dream from her. When she reapplied, he was relieved, which is why he made no objection. Jadzia tells him that the best way to act on his love for her is to rejoin her, so they can live together through Dax. Curzon agrees and rejoins her.

Nog passes his exams this time, and Rom presents him to the bar dressed in a cadet's uniform. Nog orders a root beer from Quark, who can't contain his disapproval. Meanwhile, Odo apologizes for his behavior as Curzon but has now gained a better understanding about humanoids. He marvels that Curzon was a great man, and Dax responds, "Yes... he ''is''!"
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!!Tropes

* ActuallyPrettyFunny: Even Sisko can't help cracking up watching Curzon/Odo screw with Quark.
* AnguishedDeclarationOfLove: Curzon admits that [[UnrequitedLove he'd always been in love with Jadzia]].
* ApologizesALot: Tobin can't go two sentences without apologizing for something. He even apologizes for apologizing.
* BerserkButton: Quark presses Rom's button hard by tampering with Nog's Starfleet exam. Nonconfrontational Rom threatens to destroy his brother's bar if Quark dares to hurt his son.
* BigBrotherIsWatching: Odo, once again. He mentions he's been observing Jadzia and Leeta spending time together. When Bashir asks if he watches everyone, Odo just says "not everyone"... then chides the doctor for what he ate for breakfast.
* BitchInSheepsClothing: After Nog "fails," Quark sympathetically says what a shame it is that Starfleet has lost out on a fine officer... it's his addendum that Nog will always have a place at the bar which tips Rom off.
* BodySurf: The Guardian allows the personalities of Dax's previous hosts to move into different bodies.
* BreatherEpisode: Things get real next episode.
* CanonDiscontinuity: Apparently, [[Recap/StarTrekDeepSpaceNineS02E04InvasiveProcedures Verad]] doesn't count as a previous host, though one could handwave that as Verad only being joined with Dax for only a few hours, far less than the 93 hours it takes for a joining to become permanent.
* ChangeTheUncomfortableSubject: The first time Jadzia tries to ask why Curzon let her back into the program, he immediately points out a tongo-hustler he'd like to clean out.
* TheCharmer: Curzon. Sisko says that he would cross the line into ManipulativeBastard from time to time, however, and that confronting him was the only way to deal with it.
* CharacterizationMarchesOn: In "[[Recap/StarTrekDeepSpaceNineS03E04Equilibrium Equilibrium]]," Joran is established as a tragic, tortured figure who resorted to violence when his life's ambition was taken from him. In the end, Jadzia welcomes him into her consciousness, and they embrace to become one. Here, Joran is virtually reimagined as a cold, creepy psychopath who immediately tries to harm Jadzia purely ForTheEvulz.
* ContinuityNod: One that goes right back to [[Recap/StarTrekS1E10TheCorbomiteManeuver the early days of Trek]] -- Curzon orders two tranyas from Quark. Evidently the First Federation maintains trade relations with the other Alpha Quadrant races.
* CoolOldLady: Lela, the first Host. A jovial old granny type.
* CreepyMonotone: The brief return of Joran has him speak in one. Coupled with EvilIsHammy.
* DidntSeeThatComing: Invoked. For the stress test, Nog had been practicing in the shuttle. Then O'Brien brings up the test and he's in Ops with a different problem than he practiced for. It wouldn't test his response to stress if they gave him what he prepared for.
-->(simulated Ops shakes) '''Nog:''' What was that?!
-->'''O'Brien:''' You tell me.
* DontYouDarePityMe: Jadzia is upset when Curzon says he let her back into the initiate program because he felt sorry for her.
* FakeActionPrologue: The episode begins with Nog dodging Cardassians in a runabout--until Jake appears in the windshield, at which point Nog [[ProsceniumReveal ends the program]].
* FightingFromTheInside: Sisko wins out over Joran, with a little help from Jadzia.
* FusionDance: The Composite form for Curzon/Odo, and the Switcher for everyone else.
* HannibalLecture: The scene between Jadzia and Joran, which certainly plays out like ''Film/SilenceOfTheLambs''.
* TheHedonist: Torias spends his time in Bashir's body eating, claiming life's too short to deny the pleasures.
* HotForStudent: The ''actual'' reason Jadzia was originally washed out of the program by Curzon: It was never because she wasn't good enough. It was because Curzon had fallen in love with her. It's also a part of why Curzon didn't want to go ''back'', because Jadzia would now have to deal with those memories.
* InformedAttractiveness: Jadzia's looks play a prominent role in this episode. Joran remarks on her beauty, and Curzon admits that he also found her beautiful and fell in love with her.
* KarmaHoudini: Curzon Dax torpedoed a perfectly qualified candidate (Jadzia) because he couldn't deal with his own feelings for her, a blatantly unethical abuse of his position, yet he seems not to have suffered any sanction for it during his life.
* LampshadeHanging: Bashir expresses his surprise that Leeta is going to be joining them as one of Dax's "closest friends," nodding to the fact that the writers included her because they were just stuck for any other female character. Odo replies that he's seen the two of them hanging around lately (and offscreen).
* LargeHam: Channeling the previous hosts of Dax gives everyone license to ham it up, especially Odo channeling Curzon. Sisko-as-Joran is a particularly creepy slice of ColdHam.
* LetUsNeverSpeakOfThisAgain: Quark would prefer Jadzia never tell anyone he was host to one of the female personalities and spent time combing Jadzia's hair.
* ManHug: Sisko and Curzon/Odo share a couple warm hugs upon seeing each other again.
* NoodleIncident: Curzon starts talking about a girl that Sisko got involved with at Pelios in front of Jake, prompting Sisko to [[ChangeTheUncomfortableSubject suggest that they head over to Quark's]] so Jake can finish his homework.
* ObviousStuntDouble: The stuntman who fills in for Avery Brooks during the fight between Joran and Dax doesn't look much like him.
* PapaWolf: Rom has no problem putting up with Quark's crap. Then Quark sabotages Nog's Starfleet test. And Rom gives Quark quite the shellacking.
-->'''Rom:''' My son's happiness is more important to me than anything, even ''latinum!'' Remember that, brother!
* PostKissCatatonia: Curzon/Odo invokes this in Quark just for a laugh.
* TheReasonYouSuckSpeech: Joran gives one to Jadzia. The fact that it's coming out of {{S|caryBlackMan}}isko's mouth makes it even creepier.
* ReasonableAuthorityFigure: When Rom figures out that Quark sabotaged Nog's test, Sisko allows him to retake it.
* {{Retcon}}: In the ''[[Series/StartrekTheNextGeneration Next Generation]]'' episode "[[Recap/StarTrekTheNextGenerationS2E12TheRoyale The Royale]]," Captain Picard mentions that UsefulNotes/FermatsLastTheorem has still not been proven by the 24th century. A few years after that episode was aired, Andrew Wiles was able to prove it. This episode acknowledges Wiles' proof, though it also tries to {{handwave}} Picard's comment by suggesting that mathematicians are still trying to find a better way of proving the theorem (which is perfectly reasonable, as Wiles used several techniques that hadn't been developed in Fermat's time).
* ScrewTheRulesIMakeThem: When Quark threatens to call security on Curzon/Odo to get him to end the late-night tongo game, the response he gets is, [[IAmTheNoun "I AM security."]]
* SomethingOnlyTheyWouldSay: Sisko proves that he's retaken control from Joran when he calls Jadzia "Old Man".
* StarvingArtist: When Quark tells Nog that being a Starfleet officer brings no profit and that he should follow Jake's example instead, Nog points out that Jake wants to become a writer, which isn't exactly a sure-fire way to profit either. Quark suggests he could make some money writing holodeck programs, especially the [[TheInternetIsForPorn more 'intimate' ones]].
* TechnicallyNakedShapeshifter: Curzon uses Odo's shapeshifting ability to change his outfit, since it's all Odo's body anyway.
* WhatTheHellHero: Sisko says that whenever Curzon stepped out of bounds, he would call him out on it. This is how Jadzia convinces him to reveal why he was so reluctant to allow his consciousness to rejoin the Dax symbiont.
* WhyAreYouNotMySon: Quark wants Nog to follow Jake's lead and stay out of Starfleet.
--> '''Quark:''' Why can't you take after your friend here? He knows enough to stay ''out'' of Starfleet. Even a [[FantasticSlur hew-mon]] can see that there are a lot more profitable opportunities out there for a young man with ambition.
* WorkHardPlayHard: Curzon, apparently. Despite staying up all night drinking and gambling, he still found time to get his work done.
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