I remember reading the following way way back in the early days of the internet, I think it was presented as having been transcribed from a early-80s magazine but that might not be true.
Spoiler
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FROM THE DESK OF GEORGE LUCAS
TO: ALL STAFF MEMBERS
THE PLOTS AND CHARACTERS OF OUR SPACE FILMS ARE GETTING SO CONFUSING THAT SOMETIMES EVEN I CAN'T KEEP TRACK OF WHAT'S GOING ON.
SO I'VE PUT TOGETHER THIS BOOKLET OUT OF THE STUDIO. IF AUDIENCES KNEW IN ADVANCE WHAT WE'RE PLANNING, IT COULD RUIN US.
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Altogether, there will be 12 films in our epics space saga, but they will not be made in chronological order. "Star Wars" and 'The Empire Strikes Back," our first two movies, are actually No. 5 and No. 6 in the series.
Our third picture (really No. 2 in the series) will be "Send in the Clones", in which we find out that both Darth Vader and Obi-Wan Kenobi were cloned by the same donor, who happens to be a long-lost grandfather of Chewbacca's. This sets up a conflict between the Wookiees and the Empire, which becomes the plot for our fourth film (No. 3 in the series) "Makin' Wookiee."
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After seeing "The Empire Strikes Back", some people got the idea that Darth Vader is Luke Skywaker's real father. Although "Makin' Wookiee" doesn't clear this up, it does reveal how an ancestor of Princess Leia befriends Yoda, who organizes the Jedi Knights, comprised of Darth Vader (then a young idealist in love with Lando Calrissian's great-aunt) and Obi-Wan Kenobi, who defend the Wookiees when their home, the planet Kashyyyk, is overrun by droids (film No. 11, "Cut and Droid")
This ties in neatly with our ifth film (No. 1 in the series), "A Matter of Life and Darth", in which Luke, who has unraveled the secrets of time travel (in "Makin' Wookiee"), learns that Darth Vader is a half-droid and may be the real father of both Han Solo and C-3PO. Luke gets this information from Yoda, who reveals that Darth Vader, being part droid, distrusts humans and plans to organize all the droids in the hope of destroying the Rebel Alliance.
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Meanwhile, in our sixth film, "Hiya, Leia" (No. 10 in the series), Princess Leia discovers that her grandfather and Han Solo's grandmother were next-door neighbors on Alderaan, before it was blown up by Darth Vader (in "Star Wars"). In a wild, galactic battle, Luke fights Boba Fett, and we are left with the impression that Boba may be Luke's father.
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This brings us to our seventh film, "Cut and Droid" (No. 11 in the series), which recounts the Great Droid War, in which C-3PO apparently dies, after a valiant battle against rust. This should not be confused with the plot of our eight film, "Look Ma, No Han" (No. 9 in the series), In which Han Solo in forced to become an undercover agent for Darth Vader, and is lost in hyperspace after R2-D2 reveals that Princess Leia may be the daughter of Obi-Wan Kenobi from his first marriage to a sister of Boba Fett's great-grandmother.
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Both Boba Fett and Jabba the Hutt (who are introduced in "The Empire Strikes Back") were once comrades of Darth Vader, and this is brought out in our ninth film, "Yessir, That's My Boba" (No. 4 in the series). We find out that Luke Skywalker's lightsaber was once recharged by Boba Fett's father, who we suspect may be Chewbacca. This ties in with the romance between C-3PO (who learns hes part human) and Chewbacca's half-hairy sister, Varga (introduced in "Cut and Droid").
Here we learn from R2-D2 (who holds the entire story of the Galaxy in his memory banks) how the Jedi Knights were disbanded and also observe C-3PO's nervous breakdown, when he finds out that mixed marriages sometimes don't work.
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However, we always come back to the question of who's Luke's father, and in our tenth film, "Lando Plenty" (No. 8 in the series), we discover that Lando Calrissian's great-aunt (whom we met in "Makin' Wookiee") may have been the wife of Obi-Too Kenobi (Obi-Wan's younger brother) in Cloud City, when Lando's father joined forces with a cousin of Han Solo's to put down the First Droid Uprising, which let to the Great Droid War (seen in "Cut a Droid").
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We learn more about Luke's ancestry in our eleventh film, "Space 'n Vader" (No. 7 in the series) as the Jedi Knights split into three factions - one loyal to Princess Leia, another loyal to Darth Vader, and a third having no opinion.
Luke returns from a space yoyage to the planet Kashyyyk where he discovers the true identity of his father while rescuing Chewbacca from midget aliens. Luke, as it turns out, lived as a young boy with the Wookiees, who snatched him from a drone spaceship just outside the Mandalore System, the home of Boba Fett and other Super Commandos. The Wookiees gave Luke the name of "Skywalker" which, in Wookiee tongue, means "Hairless Warrior Who Destroys Evil With Beam Of Light". Now Luke learns from R2-D2 that neither Darth Vader, Obi-Wan Kenobi, nor Boba Fett is his father.
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In our twelfth film, "Once a Knight is Enough" (No. 12 in the series), the identity of Luke's father is finally revealed. It is none other than the force, which as we learned in "Send in the Clones", was once capable of taking human form before it dissolved into the Sixth Dimension. Luke is reunited with Princess Leia (who left Darth Vader after being forced to marry him in "Heya, Leia") and they move to another galaxy.
This last film serves as the climax to the "Star Wars Saga - Part I." Immediately after it is completed (we figure that to be sometime around the year 2014), we will begin work on the 24 films that make up the "Star Wars Saga - Part II".
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