UPDATE: This story was published just prior to learning that Star Wars icon Carrie Fisher has past away due to complications from a heart attack at the age of 60. At the time of Rogue One's production, the actress was still alive. It is not believed that she participated in the VFX process for Rogue One or her scene in the movie. The following story addresses what some fans have called the unethical on-screen resurrection of Peter Cushing as Grand Moff Tarkin. At the time of the production, Carrie Fisher's 19-year-old likeness was utilized in the movie, giving the actress a digital 'facelift'. No disrespect is to be inferred when referencing the late Carrie Fisher in this story.

ORIGINAL STORY: As it soars past $500 million at the worldwide box office, Rogue One: A Star Wars Story is being heralded as a success both critically and financially, and most importantly, it's a hit where it counts, with the fans. But it hasn't been without its backlash, the biggest coming with the resurrection of one major character, and the de-aging of another, all done with CGI. SPOILER ALERT! If you haven't seen the movie yet, director Gareth Edwards and this team of mad scientists were able to bring iconic actor Peter Cushing back from the grave to reprise his role as Grand Moff Tarkin and they gave Carrie Fisher's Princess Leia a 19-year-old rebuff by way of digital facelift. And to say it has rubbed some fans wrong is an understatement.

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It has been almost two weeks since the general public got to see Rogue One for the first time. And while Edwards has discussed the arduous process and controversy surrounding Peter Cushing's performance from beyond the grave, it is only now that the rest of the team at Lucasfilm are finally opening up to the inclusion of these classic characters. The New York Times brings this expose on one of the year's most controversial movie subjects. And it does add some much needed insight into the development and decision process.

Speaking out are some of the prominent contributors who give their own accounts as to how these controversial cameos came to be. It took some great advances in digital effects to get both Tarkin and Leia back in the movie, as they appeared way back in 1977. Some have wondered why the movie even needs these characters in the first place. It wasn't an outright necessity in some fans' eyes. Producer and head of Lucasfilm's Story Group Kiri Hart claims that Grand Moff Tarkin is actually crucial to this particular story in the Star Wars universe. Kiri explains.

"If he's not in the movie, we're going to have to explain why he's not in the movie. This is kind of his thing."

Even with the backlash, the filmmakers are constantly being asked why Porkins, a prominent X-Wing fighter seen in A New Hope, wasn't in the Battle of Scarif that ends Rogue One, even though they brought back Red and Gold Leader in a manner similar to Tarkin and Leia. They need only point to that, claiming the outcry for Tarkin would have been triple-fold. That said, no one on the Rogue One team was sure exactly how Tarkin was going to turn out in terms of the look and feel of the CG effect being used. An alternative solution had been planned. John Knoll, who first had the idea to resurrect Peter Cushing from the grave via CGI, and is a producer and CCO of Industrial Light and Magic, says this about what could have happened had the VFX not worked out.

"We did talk about Tarkin participating in conversations via hologram, or transferring that dialogue to other characters."

The process behind bringing Grand Moff Tarkin and Princess Leia back from 1977 was actually a pretty complicated one. Actor Guy Henry portrayed Tarkin on set, dressed in full Imperial uniform with motion capture rigs on his head. Knoll went onto say this.

"We're transforming the actor's appearance to look like another character, but just using digital technology. [It's] a super high-tech and labor-intensive version of doing make-up. When Peter Cushing makes an 'aah' sound, he doesn't move his upper lip. He only opens his jaw about halfway, and makes this square shape with his lower lip, that exposes his lower teeth. [At one point, it] looked like maybe a relative of Peter Cushing and not him exactly."

The data from the motion capture sessions was sent to ILM, where a team of VFX artists did their best to recreate Peter Cushing's nuance, which some fans have called unethical. The process actually hit a major stumbling block when it was discovered that the lighting in A New Hope was much different than it was in Rogue One. This made the challenge of perfecting the character even harder on the team.

Kiri Hart defends the use of a younger CGI Princess Leia, claiming she was as essential to this story as Tarkin, even though she only clocks in one minute of screen time. Hart explains.

"To deliver on that moment of hopefulness, that is really underscored by the fact that you do get to see her face. That's the best possible use of effects, to enhance the meaning and the emotion of the experience for the viewer."

Like Tarkin, Princess Leia was also portrayed by an actor on set, with Ingvild Deila standing in as the young Carrie Fisher. She was then digitally altered too appear as the 19-year-old Fisher as fresh as the day she first stepped on set. With Alden Ehrenreich coming into play a young Han Solo, many have wondered, though, why Leia couldn't have been recast, which a great many fans would have preferred. In terms of ethics, Knoll did respond to this particularly backlash, saying this use of CGI should only be used sparingly when it comes to future movies.

"[It is a] slippery slope argument...[It is] in the spirit of what a lot of Star Wars has done in the past...It is extremely labor-intensive and expensive to do. I don't imagine anybody engaging in this kind of thing in a casual manner. I don't imagine that happening. This was done for very solid and defendable story reasons. This is a character that is very important to telling this kind of story. We're not planning on doing this digital re-creation extensively from now on. It just made sense for this particular movie."

It is possible that Princess Leia could return for a future Star Wars spin-off. And if that happens, the character will likely be recast. At this time, there are no plans to bring Tarkin back for a big screen movie, but he has been and will continue to be a part of the Star Wars Rebels line-up, appearing as a secondary character on occasional episodes. When it came to Rogue One, the team assures that it lived by this golden rule, 'Realism had to trump likeness'.

Knoll ends his discussion by assuring fans that in 50 or 100 years, audiences will probably not see Mark Hamill or Harrison Ford playing Luke Skywalker or Han Solo in this same manner. But by that time, there will have definitely been a passing of the guard, and if they're doing it now, really, what will stop the next team from contemplating or doing the same?