But Disney and J.J. Abrams scrapped most of those plans while working on Star Wars: The Force Awakens.
Rian Johnson's film in the franchise seems to have taken inspiration from Lucas' own work, however, as evidenced by The Art of Star Wars: The Last Jedi, which might be the only place fans can see a version of the sequel films that will never come to be.
The book reveals Lucas himself held one of the first meetings to visualize Episode VII at Skywalker Ranch, where a few different pieces of concept art were shown of Luke Skywalker and a young woman named Kira, the first iteration of the character who would become Rey, in an ancient Jedi temple.
These ideas were shelved until Star Wars: The Last Jedi, of course, as The Force Awakens became a film about Rey taking her first steps into a larger world with the guidance of reluctant mentor Han Solo.
A lot of the bones for Luke's journey were set up from Lucas' work, it seems. Luke found himself in a dark place 30 years after the events of Return of the Jedi. Through the course of the film, the Jedi Master would once again realize his mission and began training a young Force-sensitive woman in an ancient Jedi temple.
There were also pieces showing Luke possibly being haunted by old Sith ghosts, teasing that the final battle for the Jedi would actually take place in the spirit realm. That particular concept was never fleshed out, though it was heavily rumored before the film's release.
While the current sequel trilogy seems to be going in a drastically different direction from what Lucas began to envision, Rian Johnson's film has built off of those basic ideas in new and interesting ways.
It's unlikely we'll ever see Lucas making another Star Wars film in the future; this artwork is likely the closest fans will get to seeing his version of the events after Return of the Jedi.
Star Wars: The Last Jedi is now playing in theaters everywhere.