"The Jem'Hadar" is the 26th and final episode in the second season of the syndicated American science fiction television series Star Trek: Deep Space Nine, the 46th episode overall. It introduces the Jem'Hadar and the Vorta, two species of the Dominion (which was previously hinted at in the episode "Rules of Acquisition").

Set in the 24th century, the series follows the adventures on Deep Space Nine, a space station located near a stable wormhole between the Alpha and Gamma quadrants of the Milky Way Galaxy. In this episode, the crew of DS9 meets a force more powerful than the Federation.

Commander Sisko and his son Jake are preparing for a father-son camping trip to a planet in the Gamma Quadrant. Sisko is disappointed when Jake invites his best friend Nog to join them, and even more dismayed when Nog's uncle Quark invites himself along as well. They depart as planned, but as they set up camp, Quark quickly becomes irritated by the environment, and argues with Sisko, leading an embarrassed Nog to storm off into the woods, with Jake chasing after him.

Sisko and Quark are startled when an alien woman comes running out of the forest, pursued by a troop of fierce soldiers, who take all three captive. Sisko, Quark and the woman, Eris, are taken to a cave where they are imprisoned in a force field. Eris warns Sisko that the field is lethal, and that she is unable to use her telekinetic abilities to disable it due to the suppressive collar around her neck. She explains that the soldiers are Jem'Hadar, bred and put into service by the Dominion, who rule that section of the Gamma Quadrant, and that they cannot be escaped or defeated. Sisko points out that they have been imprisoned together and are not under close guard, believing that he can use their captors' apparent overconfidence to their advantage, and begins by attempting to remove Eris' collar.

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