Obi-Wan Kenobi is introduced in the original "Star Wars" film living as a 57-year old hermit by the name of Ben Kenobi on the planet Tatooine. When Luke Skywalker (Mark Hamill) and C-3PO (Anthony Daniels) travel the desert in search of the lost R2-D2 (Kenny Baker), Obi-Wan rescues them from a band of Tusken Raiders by imitating the call of a Krayt dragon. At Obi-Wan's home, the now-found R2-D2 plays a recording of Princess Leia (Carrie Fisher) saying that R2-D2 contains the plans for the Galactic Empire's superweapon: the Death Star. 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 secret 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. He gives Luke his father's lightsaber and asks him to accompany him to Alderaan and take up Jedi training. Luke, at first, declines; but after finding that his aunt Beru (Shelagh Fraser) and uncle Owen (Phil Brown) have been killed by Imperial stormtroopers, he realizes he must go with Obi-Wan to Alderaan and to train as a Jedi.