"Emissary" is the series premiere of the American science fiction television series Star Trek: Deep Space Nine. It was aired as a single two-hour episode on its initial broadcast, but was divided into two one-hour episodes when it aired in reruns.

Set in the 24th century, the series follows the adventures on Deep Space Nine, a space station located near the planet Bajor, as the Bajorans recover from a brutal decades-long occupation by the imperialistic Cardassians. In this premiere episode, Commander Benjamin Sisko (Avery Brooks) and his son Jake (Cirroc Lofton) arrive with Starfleet personnel on the station shortly after Cardassian occupation forces have departed. While working to repair the station and assist the Bajoran people, Sisko discovers an unprecedented wormhole connecting Bajor to the distant, unexplored Gamma Quadrant of the galaxy and the mysterious, incorporeal beings that inhabit it.