Overview
"The Vengeance Factor" is the ninth episode of the third season of the American science fiction television series Star Trek: The Next Generation, and the 57th episode of the series overall. Captain Picard contends with a divided people, the Acamarians. In this episode, the crew of the Enterprise tries to negotiate an end to raids launched by a group called the "Gatherers," but a murder threatens to prevent peace. Several guest stars are featured as Acamarians.
Plot
The Enterprise travels to the planet Acamar III after detecting traces of Acamarian blood at a looted Federation outpost. Sovereign Marouk, the Acamarian leader, suggests that the looting was done by the Gatherers, descendants of Acamarian society a century ago that have turned to piracy to sustain themselves. Marouk initially suggests hunting them down with the help of Starfleet, but Captain Picard convinces Marouk to join him to seek a peaceful resolution, including ending the Gatherers' self-imposed exile. Marouk and her assistant, Yuta, arrive on the ship to help. Commander Riker finds Yuta attractive and tries to get to know her better, but Yuta finds herself unable to open up to him.
The Enterprise crew makes contact with one band of Gatherers led by Brull, and offer negotiations. Brull negotiates with Marouk and Picard, and after hearing the offer, agrees to pass it on to the Gatherer leader, Chorgan. Meanwhile, Yuta meets alone with one of the older Gatherers and touches his cheek, causing the Gatherer to suffer a heart attack. As the man dies, Yuta asserts that she, as the last of her clan, Tralesta, will outlive the Lornak clan. The Gatherer's body is later found but initially assumed that death was by natural causes. However, later investigation by Dr. Crusher reveals that a fast-acting "micro-virus", targeted to attack a specific Acamarian DNA profile, was the cause. Dr. Crusher believes the virus was purposely genetically engineered, and that the death was a targeted murder. At Picard's request, Marouk has her government send data to the Enterprise to investigate the murder.
The Enterprise meets with Chorgan's starship, and Picard, Marouk, and Yuta transport aboard to begin negotiations. At the same time, the Enterprise crew receives the database from Acamar, and find that fifty-three years earlier, another Gatherer suffered a similar heart attack - he too was from the Lornak clan, and a photographic record shows Yuta was present, and clearly hasn't aged a day.
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