Guinan is a character on Star Trek: The Next Generation portrayed by Whoopi Goldberg.
She is a member of a species of "listeners" that was scattered throughout the galaxy when the Borg destroyed their homeworld. She is known to have visited San Francisco on Earth in the late 19th century, where she assisted the crew of the Enterprise-D (who had traveled back in time from the 24th century), meeting Jean-Luc Picard for the first time.
Guinan was aboard an El-Aurian transport vessel trapped in an energy ribbon known as the Nexus for some time. In 2293 she was "rescued" from it by the Enterprise-B. Roughly seventy years later, she ended up on the Enterprise-D, serving up drinks and advice in the Ten-Forward lounge.
Besides the Borg, Guinan has some other enemies, such as Q, who has some history with Guinan and was responsible for introducing the Borg to humanity (prompting the tragedy at Wolf 359 and the events in Star Trek First Contact).
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