Pre-production for Rogue One: A Star Wars Story began as early in 2014, when Disney announced that Gareth Edwards would be the director of the first stand-alone film in the beloved sci-fi saga. Filming began in the summer of 2015, which gave Disney a year and a half to make the entire thing before its December release date. But in May of 2016, reports indicated the film was in trouble and needed substantial reshoots.

As it turns out, they were adding substantial new scenes to the film within weeks of the release date. One of those was Darth Vader's big scene in what were arguably the best five minutes of Rogue One. As Edwards told Fandango, the Vader scene was a completely last-minute idea:

He arrives and obliterates the Calamari ship, and then the blockade runner gets out just in time and he pursues the blockade runner. And then [editor] Jabez [Olssen] was like, "I think we need to get Darth on that ship," and I thought, yeah, that's a brilliant idea and would love to do it, but there's no way they're going to let us do it. It's a big number and we had, what, like three or four months before release. Kathy [Kennedy] came in and Jabez thought, fuck it, and pitched her this idea, and she loved it. Suddenly within a week or two, we were at Pinewood shooting that scene.

They pulled it off, but only barely.

As we've already learned, these late reshoots completely reshaped the final movie. The ending in particular changed quite a bit, with many fans speculating that some of the characters originally lived through the movie. These reshoots also added in more background to Jyn's character so it—you know—kind of made sense.

Some of the many gaping flaws aside, Rogue One succeeded in at least being a pretty great action movie. But most of this is thanks to the final act, which was completely reshaped at the very last minute. There was a lot riding on this movie: It cost a shit ton of money! It would set the tone for the rest of Disney's stand-alone Star Wars films! It's part of one of the most beloved movie franchises of all time! So it's surprising to see the film patched together this late in the process. Hopefully, Disney learned something, at least, going into the next stand-alone Star Wars movies.

From: Esquire US