The Story: Back-story. It was all-important in Star Wars (as it was known back then, before it became Star Wars: Episode IV—A New Hope). It's what made the movie really interesting, and ultimately locked it into a course from which it couldn't move past, cemented it as if if had been frozen in carbonite.
And, with the budget had—a relatively paltry 10 million dollars (the same budget 2001: A Space Odyssey had ten years previously)—all George Lucas could do was talk about it.
So, this scene did a lot of duty in a short period of time. While we were learning about the cruelty of Darth Vader and Grand Moff Tarkin (up there in orbit on their Battle Cruiser) on a parallel time-track, Luke had a mystery to solve, and it's all solved...and made much more complicated in this scene, having found the man he's after, "Old Ben" Kenobi.
The story is, he was supposed to seem a little crazy at first, but Alec Guinness didn't want to play it that way—this was at a time when Lucas could be overruled—and Lucas let the veteran actor play it his way—dignified and a little unscrupulous (the "crazy" aspect would be transferred to Yoda, when Luke first meets him in The Empire Strikes Back).
And it paid off in spades, producing a pivotal moment—"a happy accident"—that Lucas took advantage of in deepening the story: the weighty hesitation that Kenobi has before telling Luke the fate of his father—the spinning of the tale that it was Darth Vader who killed his father, true "from a certain point of view."
Or was it "a happy accident?"
An issue of Psychology Today, that came out quickly once Star Wars became a cultural phenomenon, drew parallels with The Wizard of Oz, and noted that "Darth Vader" was a Germanic distillation of "dark father," making the Old Sith-heel an apposite father figure in Luke's life-journey. Two years before the revelations of Empire, they hit it on the nose of the wheezing face-plate.
Bear in mind that, even though we know nothing of Obi-Wan except what he tells us, we don't know what he knows. And he knows everything. He knows who Luke is, who his father is, and the whole sordid story, and has been biding his time until this moment of connection. This is what he's been waiting for, hiding out, for the last 20 years. So, he's a little pushy, manipulating Luke in the direction of His Destiny, smiling as Luke falls right into the inquiry about "The Force," applying "The Guilt" when necessary, and using psychology rather than a "Jedi mind-trick."
At the time of the first movie, all this past was in the future, and this was just a pause for exposition. In retrospect, it's a heady scene. Did Lucas know all this when the scene was written and shot?
Does it matter?
The Set-Up: Young Luke Skywalker (Mark Hamill) has had the entire Universe fall from the sky into his care. Two droids have crashed on the planet Tatooine, that have information that could prove the undoing of the Galactic Empire's most vicious weapon, the marauding planet-killer, The Death Star. By chance, the droids, with the enigmatic holographic message from an unknown dignitary (Carrie Fisher), have made their way to him, and he has followed them to their intended receiver, General Obi-Wan Kenobi (Alec Guinness), who has resided for many years on the planet as "a crazy old hermit." But, soon, the answers—and many more questions—will be revealed on Skywalker's Hero Quest.
The small, spartan hovel is cluttered with desert junk but still manages to radiate an air of time-worn comfort and security. Luke is in one corner repairing Threepio's arm, as old Ben sits thinking.
LUKE: No, my father didn't fight in the wars. He was a navigator on a spice freighter.
BEN: That's what your uncle told you. He didn't hold with your father's ideals. Thought he should have stayed here and not gotten involved.
LUKE: You fought in the Clone Wars?
BEN: I was once a Jedi Knight the same as your father.
LUKE: I wish I'd known him.
BEN: He was the best star-pilot in the galaxy...
BEN:...and a cunning warrior.
BEN: I understand you've...
BEN: ...become quite a good pilot yourself.
BEN: And he was a good friend.
BEN:Which reminds me...
Ben gets up and goes to a chest where he rummages around. As Luke finishes repairing Threepio and starts to fit the restraining bolt back on, Threepio looks at him nervously. Luke thinks about the bolt for a moment then puts it on the table. Ben shuffles up and presents Luke with a short handle with several electronic gadgets attached to it.
BEN: I have something here for you.
BEN: Your father wanted you to have this when you were old enough...
BEN: ...but your uncle wouldn't allow it.
BEN: He feared you might follow old Obi-Wan...
BEN: ...on some damned-fool crusade like your father did.
THREEPIO: Sir, if you'll not be needing me, I'll close down for awhile.
LUKE: Sure, go ahead.
Ben hands Luke the saber.
LUKE: What is it?
BEN: Your father's lightsaber. This is the weapon of a Jedi Knight.
BEN: Not as clumsy or as random as a blaster.
Luke pushes a button on the handle. A long beam shoots out about four feet and flickers there. The light plays across the ceiling.
BEN: An elegant weapon for a more civilized time.
BEN: For over a thousand generations the Jedi Knights were the guardians of peace and justice in the Old Republic.
BEN: Before the dark times, before the Empire.
Luke hasn't really been listening.
LUKE: How did my father die?
BEN: A young Jedi named Darth Vader, who was a pupil of mine until he turned to evil...
BEN:...helped the Empire hunt down and destroy the Jedi Knights.
BEN: He betrayed and murdered your father.
BEN: Now the Jedi are all but extinct.
BEN: Vader was seduced by the dark side of the Force.
LUKE: The Force?
BEN: Well, the Force is what gives a Jedi his power.
BEN: It's an energy field created by all living things. It surrounds us and penetrates us.
BEN: It binds the galaxy together.
Artoo makes beeping sounds.
BEN: Now, let's see...
BEN: ...if we can't figure out what you are, my little friend.
BEN: ...And where you come from.
LUKE: I saw part of the message he was...
Luke is cut short as the recorded image of the beautiful young Rebel princess is projected from Artoo's face.
BEN: I seem to have found it.
Luke stops his work as the lovely girl's image flickers before his eyes.
LEIA: ...years ago you served my father in the Clone Wars.
LEIA: Now he begs you to help him in his struggle against the Empire. I regret that I am unable to present my father's request to you in person...
LEIA: ...but my ship has fallen under attack and I'm afraid my mission to bring you to Alderaan has failed.
LEIA: I have placed information vital to the survival of the Rebellion into the memory systems...
LEIA: ...of this R2 unit.
LEIA: My father will know how to retrieve it.
LEIA: You must see this droid safely delivered to him on Alderaan. This is our most desperate hour.
LEIA: Help me, Obi-Wan Kenobi, you're my only hope.
There is a little static and the transmission is cut short.
Old Ben leans back and scratches his head. He silently puffs on a tarnished chrome water pipe. Luke has stars in his eyes.
BEN: You must learn the ways of the Force if you're to come with me to Alderaan.
LUKE: (laughing) Alderaan?
LUKE: I'm not going to Alderaan. I've got to go home.
LUKE: It's late, I'm in for it as it is.
BEN: I need your help, Luke. She needs your help.
BEN: I'm getting too old for this sort of thing.
LUKE: I can't get involved! I've got work to do!
LUKE: It's not that I like the Empire. I hate it!
LUKE: But there's nothing I can do about it right now.
LUKE: It's such a long way from here.
BEN: That's your uncle talking.
LUKE: (sighing) Oh, God, my uncle.
LUKE: How am I ever going to explain this?
BEN: Learn about the Force, Luke.
LUKE: Look, I can take you as far as Anchorhead.
LUKE: You can get a transport there to Mos Eisley or wherever you're going.
BEN: You must do what you feel is right, of course.
STAR WARS: Episode IV—A NEW HOPE (From THE JOURNAL OF THE WHILLS)
Words by George Lucas
Pictures by Gilbert Taylor and George Lucas
Star Wars: Episode IV—A New Hope is available on DVD (in all sorts of versions) on 20th Century Fox Home Video.