After Anakin turns to the dark side and his wife, Padmé Amidala, dies in childbirth in "Revenge of the Sith," their twins are separated at birth in order to keep them safe from the Empire, who are still hunting down every last force user in the galaxy. Their daughter, Leia, is adopted by Senator Bail Organa and his wife, Breha Organa, on Alderaan. Meanwhile, Anakin and Padmé's son, Luke, goes to live on Tatooine with his uncle Owen (aka, Anakin's stepbrother) and aunt Beru. Since Luke is believed to be the galaxy's next hope, Obi-Wan watches over him from a distance in order to make sure he remains safe from the Empire, which you can catch a peak of in the trailer.
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