George Lucas wanted to add shots to The Empire Strikes Back after it had already screened. The crew at Industrial Light and Magic thought the director was kidding, but he was far from joking. The highly anticipated sequel had already been showing on about 100 screens by this point and was three weeks away before its official premiere, according to the official Star Wars website. The Empire Strikes Back is currently celebrating its 40th anniversary, which is why we're hearing about all of this now.

In May 1980, Industrial Light & Magic's general manager Tom Smith received a phone call from George Lucas. Smith recalled the startling conversation to Lucasfilm executive editor J.W. Rinzler, who is also the author of The Making of The Empire Strikes Back. He told Rinzler what Lucas had told him, "I don't wanna tell you this. We need some more shots for Empire." Smith thought it was a joke since they were done and the movie was in theaters. "No, no, no," Lucas declared, "it's not in all the theaters."

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So, what did George Lucas want to go back and add to The Empire Strikes Back? Apparently Lucas "realized that the end of the film was unclear," during a screening because it was not clear that Lando Calrissian and Chewbacca were on a different ship from Luke and Leia at the end of the movie. After they escape from Cloud City, Luke has his new hand and is recuperating, while Chewie and Lando prepare to set off in the Millennium Falcon to head to Tatooine.

Tom Smith and Industrial Light and Magic went to work to add the missing shots in The Empire Strikes Back, satisfying George Lucas and getting rid of any possible confusion. It's now clear that Luke and Leia were on the medical frigate, while Chewie and Lando were in the Millennium Falcon. There's certainly no confusion now, and it's not really clear if Star Wars fans would have had any confusion had they left the movie the way it was. Whatever the case may be, George Lucas was very happy to have it completed the way he wanted. At least for 1980, since he went back and made some changes in the 1990s too.

The Empire Strikes Back is often regarded as the best Star Wars movie, or at least second best to A New Hope. It has a darker storyline and fans were introduced further into the ways of the Force, thanks to a little green Jedi Master named Yoda. We learned that Darth Vader is Luke Skywalker's father. It's a heavy movie, filled with inventive and unexpected storyline twists that have largely been absent from the later installments, even the prequels, which George Lucas worked on. You can head over to the official Star Wars website to celebrate the 40th anniversary of The Empire Strikes Back.