In this episode, Jadzia Dax undergoes a Trill rite of closure that brings her face to face with the past hosts of her symbiont, forcing her to deal with feelings of inferiority as a Dax host herself. Also, Nog takes a simulator test as part of his Starfleet Academy admissions process, much to the dismay of his Uncle Quark.

Jadzia Dax finally makes plans to undergo her Zhian'tara, in which she has the chance to actually meet her previous hosts by temporarily transferring each one's memories from the symbiont into the minds of each of her closest friends.

The Zhian'tara is the Trill rite of closure. This is an emotionally intense ceremony which involves the separation of the personalities of the previous hosts from the symbiont into friends of the current host. The relation allows the current host to gain a renewed sense of his/her shared lives. The process takes place with the assistance of a Guardian who telepathically transfers the personalities. Commander Sisko, Major Kira, Dr. Bashir, Odo, Quark, Chief O'Brien, and Leeta have agreed to participate.

Kira accepts Lela Dax, and Jadzia can see that she is the origin of many of Dax's unique characteristics, which she herself now exhibits. O'Brien becomes the shy but friendly Tobin Dax. Leeta receives the personality of Emony Dax, a cheerful and talented gymnast. Quark had been somewhat nervous about taking on the personality of the female Audrid Dax, who tenderly brushes Jadzia's hair as they talk. Bashir is Torias Dax, an adventurous pilot who died young in a shuttle accident. Sisko has to be restrained in a holding cell to receive the personality of Joran Dax, who was a violent murderer. Indeed, when Jadzia comes to meet him he tricks her to lower the force field between them, and grabs her and tries to strangle her. After a brief struggle, Sisko regains control of his body. Verad (cf. Season Two's "Invasive Procedures") is not among the previous hosts that are separated out, since Verad stole the Dax symbiont and was not joined long enough to be a true host.

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