Answering a distress call from a planet under attack by the Borg, the U.S.S. Enterprise meets Delcara, the lone survivor of an alien race the Borg obliterated. Blinded by hatred, Delcara seeks the ultimate revenge, the complete destruction of her race's executioners. But the U.S.S. Enterprise crew learns that Delcara's vengeance carries a terrible price, for once unleashed, the destructive force she commands will annihilate not only the Borg, but countless innocents as well.
(From the Star Trek Series shelf.)