Captain Wrack was an Eternal who participated in the race across the solar system for Enlightenment, believing that it would rid her of her dependence on the minds of Ephemerals and allow her to create and destroy as she wished. As a result, she would never again be bored.
During the race, Wrack was in league with the Black Guardian and channelled the power that he gave her to destroy her competition. Her ship, the Buccaneer, was modelled on a pirate vessel and she sabotaged her opponents' ships from a secluded room within. The Fifth Doctor and Turlough threw Wrack and First Mate Mansell overboard into space before they reached the Enlighteners. As they were Eternals, they were merely displaced and did not truly die. (TV: Enlightenment)