Jake is hanging out at Quark's while his girlfriend Mardah works the Dabo table. After bilking a gambler out of his stake, she sits with Jake and tells him that his father has invited her to dinner. Jake is surprised but optimistic. Meanwhile, a shady trader named Rionoj seduces Quark into buying some salvage sight unseen. When Quark investigates his recent purchase, he discovers to his shock that it includes an alien infant.
The whole station crew jumps into investigating the incident. Bashir says that the infant is of an unknown species with an incredible metabolic rate. Sisko is taken with the child, reminded of Jake as a baby. Speaking of Jake, Sisko plans on ending his son's relationship with Mardah after their dinner, but he wants to at least meet her first.
The baby is growing at an amazing rate. By the next day, he looks nine years old, and Bashir says that the only explanation is genetic engineering. O'Brien notes that the baby was held in stasis, apparently to prevent it from maturing during the journey. Meanwhile, Kira visits Odo at his new quarters. The constable is reluctant to invite her in, but once he does, he reveals that he's building furniture to inspire his shapeshifting abilities. No longer in need of his old bucket for his periods of liquidation, he uses it as a pot for Kira's gifted houseplant, to her approval.
Bashir discusses the alien child with Dax, noting that he lacks a critical enzyme to survive. As they wonder at the purpose of such an obvious flaw, they're called away when the boy, now a man, breaks out of the infirmary. His mature appearance answers all the mystery surrounding him: he's a Jem'Hadar. He only stops rampaging when Odo arrives, and he instinctively submits to the "changeling."
Sisko tells his staff that the nameless Jem'Hadar will be taken to a research base for study, and Kira is happy to be rid of the killing machine. Odo and Bashir, however, argue that he has rights as a sentient being. Odo knows all too well how it feels to be raised in a laboratory. He convinces Sisko to delay the Jem'Hadar's departure. In that time, Odo forces his charge to submit to Bashir's tests to replicate the missing enzyme.
At dinner, Sisko asks Mardah about herself but ends up learning more about his son. She tells him how Jake writes beautiful poetry and hustles dom-jot in his spare time. Sisko is dumbfounded and impressed.
Odo tries to take the Jem'Hadar under his wing, teaching him that changelings are no better than anyone else and that he must think for himself. The Jem'Hadar states that he wants to find his people. Odo tells him that his people are brutal warriors, but he doesn't need to be. To slake the man's thirst for violence, Odo introduces him to a training program in the holosuites, telling him that he must control himself while outside. Kira is less than impressed by this tactic. Soon afterward, Bashir manages to replicate the missing enzyme, which the crew now hypothesize was invented as a means to control the Jem'Hadar.
Odo continues trying to help the Jem'Hadar break out of his genetic conditioning for simple violence, to little success. Sisko summons Odo and announces that Starfleet is coming for the man after all, but the Jem'Hadar has been listening in. He appears and holds Sikso at phaserpoint, saying that he won't be taken prisoner. He demands access to a runabout. The crew comply. Odo tries to talk the Jem'Hadar out of it, but to no avail. Odo convinces Sisko to allow him and the Jem'Hadar to leave peacefully, assuring him that he's at no risk from his captor.
With peace restored, Sisko decides not to end Jake's relationship with Mardah after getting to know his son better. When Odo returns, he stops by Kira and admits that she was right about the Jem'Hadar all along.
- Absolute Cleavage: Mardah's outfit proves that all species value the same attributes in a Dabo girl.
- Age-Gap Romance: Sisko bristles at the thought of his 16-year-old son romancing a 20-year-old Dabo woman.
- Amazingly Embarrassing Parents: Sisko finds out from Mardah some things about Jake he didn't know, and he relishes getting all the juicy details.
- Bittersweet Ending: Odo does what he can to raise the Jem'Hadar to be more humanistic, but there's nothing anyone can do - the Jem'Hadar just can't go against his programming. Odo has to let him go to protect his fellow officers.
- Blood Knight: This episode shows that for the Jem'Hadar, fighting isn't something they do just because their masters tell them to, it's an actual physical need that is instilled in them from birth.
- Cuteness Proximity: Sisko practically turns to jelly once he gets the chance to hold the baby, to the point where he barely pays attention when Dax and Bashir give him information.
- Death Glare: When Quark protests the summary seizure of his salvage, Sisko doesn't even bother to justify his decision. He just shoots Quark a mean stare until the hapless Ferengi backs down.
- Foreshadowing: In a lunch with Dax, Bashir notes how the child seems to be missing a key enzyme and is baffled why someone would "engineer a child with such an obvious defect." This turns out to be a key clue to the boy being a Jem'Hadar, as the Founders put in their addiction.
- Hard Truth Aesop: Some people can't be saved from themselves.
- Henchmen Race: The Founders seem to have stripped everything out of the Jem'Hadar that doesn't involve fighting or obeying their creators. And they've engineered them with an innate addiction to a substance only the Founders can produce for good measure.
- Hidden Depths: Jake wanted Benjamin to get to know Mardah, but when Benjamin spends time with the two of them he's surprised to learn a few things about Jake he didn't know before, like that he sometimes writes poetry.
- Little "No": Quark, when he realizes that he accidentally bought a baby.
- Ms. Fanservice: Mardah. The fact that Jake could even look her in the eye shows Cirroc Lofton's a pretty good actor.
- The Nameless: No one gives the Jem'Hadar a name.
- Nature vs. Nurture: The main theme of the episode. Odo's a strong believer in Nurture due to his own experiences, but it turns out Nature's pretty damn strong for the Jem'Hadar.
- Orc Raised by Elves: It's tried with the Jem Hadar baby, but the Founders had genetically engineered them to hate all non-Founders, and the attempt to raise him like Worf fails.
- Out of Focus: While Quark gets more than a Mandatory Line, he's only in the beginning of the episode.
- Plot-Relevant Age-Up: The Jem'Hadar are genetically engineered to reach maturity and become battle-ready as quickly as possible.
- P.O.V. Cam: The Jem'Hadar leaving the infirmary and getting a lot of shocked and fearful looks from people on the Promenade.
- Riddle for the Ages: We never find out what the freighter was doing with an infant Jem'Hadar or what happened to it.
- Shipper on Deck: O'Brien."Sixteen years old and dating a Dabo girl. Godspeed, Jake."
- Tragic Villain: The Jem'Hadar as established as such in this episode. They are a violent race whose instincts were engineered into them, and it is played for tragedy that the Jem'Hadar in this episode can't fight against his violent nature. They are an Always Chaotic Evil race who were genetically engineered to be that way by cruel masters, and even with their instinctive Undying Loyalty the Founders still engineered them to need drugs to survive that only they can provide.
- The Un-Smile: Odo attempts to teach the Jem'Hadar to smile. The result◊ is...not pleasant.
- What the Hell, Hero?: Both Odo and Bashir are not happy with Sisko willing to give the boy over to Starfleet to turn him into a lab rat. Odo knows what that's like first-hand and how badly the boy will feel. Bashir agrees that whatever else, the Jem'Hadar is a sentient being and not just an experiment to study.