One of the most exciting, gasp-worthy moments in Rogue One: A Star Wars Story takes place in the film’s final moments. In the scene – spoiler alert – a red lightsaber slices through the darkness and Darth Vader emerges onto the ship. He demolishes a pack of rebel soldiers before a blockade runner escapes and delivers the Death Star plans to Princess Leia. It’s one of the best scenes in the film, but it almost didn’t happen.

As we previously reported in January, that climactic lightsaber duel was a last-minute addition during reshoots. But in a new interview with Fandango ahead of the film’s digital and Blu-ray release, Rogue One director Gareth Edwards reveals how the scene came about. In the original scene as it was written, Vader never appeared on the ship, but the film’s editor Jabez Olssen came up with the idea only a few months before the movie hit theaters. Gareth explained how the scene ended up happening:

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 Jabez 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 3 or 4 months before release. Kathy [Kennedy] came in and Jabez thought, f–k it, and pitched her this idea, and she loved it. Suddenly within a week or two we were at Pinewood shooting that scene.

The director calls the scene “The Walk of Death” and says he asked the stunt crew to pitch him ideas for how the duel could go down. “They came up with a whole shopping list of ideas,” he said. “Seventy percent we used, and maybe 30% felt a little too extreme. They were things you hadn’t seen him do before, and I wanted to stick to what Darth does in the original trilogy.” Edwards also wanted to make sure the scene was done right, and not haphazardly thrown in at the last minute. “We storyboarded absolutely everything and tried to have no regrets,” he added.

Rogue One is a Star Wars film that's been celebrated for taking risks, from reanimating a dead actor via CGI to the audacious style of the space battles and the Vader ending. It’s a movie that found some of its strongest moments by breaking tradition. Here’s to hoping Lucasfilm continues to take risks in future installments.

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