 Leia asks him to deliver R2-D2 and the plans safely to her home planet of Alderaan in order to help the Rebel Alliance.Obi-Wan reveals to Luke his true identity and explains that he is a Jedi, a member of an ancient group of Force-sensitive warriors.He explains that the Jedi were hunted down and exterminated by the Empire with help from his former apprentice, Darth Vader (portrayed by David Prowse, voiced by James Earl Jones), the apparent killer of Luke's father.