"Prophecy" is the 160th episode of the TV series Star Trek: Voyager, the 14th episode of the seventh season. The episode deals with Klingon religious beliefs and stem cells.

An antique Klingon D-7 class vessel attacks Voyager, cloaked. Using a metaphasic scan, Seven of Nine calculates the position of the ship, allowing Tuvok to fire on it and disable their cloaking device. The captain of the Klingon ship, Kohlar, refers to the Federation as "sworn enemies of the Empire." Naturally, Kohlar doesn't believe Kathryn Janeway when she says that the Federation and the Empire have been at peace for eighty years. However, when Kohlar sees B'Elanna Torres - who is pregnant - he abruptly changes his mind. Kohlar has his crew fake a core breach on his ship so that all the Klingons aboard are transported to Voyager. When he is confronted by Janeway about this, he explains that he believes Torres' unborn child is the prophesied "Kuvah'magh," the savior of the Klingon people, the one whom Kohlar's ancestors left the Klingon world in a multi-generational voyage in order to meet. The elder Klingons are very skeptical, especially because Torres is only half Klingon and thus her daughter will be only one-quarter Klingon. Other Klingons constantly bother Torres when she is working, prompting her to beam from place to place.

T'Greth, one of the Klingons, challenges Tom Paris, B'Elanna's husband, to a duel to the death, which Paris accepts. At Janeway's insistence, however, T'Greth and Paris agree to a non-lethal duel with blunted bat'leths. To everyone's surprise, T'Greth loses the duel.

It turns out that T'Greth suffers from a seemingly incurable disease known as Nehret, which afflicts all Klingons aboard Kohlar's ship, and now Torres and her unborn child as well. T'Greth convinces some of the other Klingons to take over Voyager. After much fighting, the Voyager crew retakes the ship. The Doctor then comes up with a cure by using stem cells from B'Elanna's baby.

The Klingons relocate to an M-class planet while Paris and Torres agree to consider "Kuvah'magh" as a possible name for the baby.

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