Here's how X-Men: The Last Stand digitally de-aged Patrick Stewart and Ian McKellan, and why it looks so bad. Directed by Brett Ratner, X-Men: The Last Stand was a blockbuster in the summer of 2006 that brought the original X-Men movie trilogy to a close. While it grossed more than the two previous films directed by Bryan Singer, X-Men: The Last Stand has a reputation as one of the worst X-Men movies, and one reason it's looked down upon today is how poor the digital de-aging effects are at the start of the film.

X-Men: The Last Stand opens with a flashback set "20 years ago" where Professor Charles Xavier (Stewart), who is able to walk, and his best friend Erik Lensherr (McKellan) visit a young Jean Grey (Haley Ramm) in order to recruit her to the Xavier School. Rather than cast younger actors in the roles - as would eventually happen when James McAvoy and Michael Fassbender took over as Professor X and Magneto in the next wave of X-Men movies - Ratner opted to utilize digital de-aging to make the two legendary actors, who were both in their mid-60s at that point, look two decades younger. The result is an unfortunate trip into the uncanny valley as both Patrick Stewart and Ian McKellan's faces were jarringly smoothed out, giving them an inhumanly plastic quality in the scene.

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To achieve the digital facelifts for X-Men: The Last Stand, Brett Ratner employed a studio called Lola, which specializes in "digital cosmetic enhancements" like the kind that had been used on musicians and singers in music videos for years. The scene was performed normally by the actors and shot in-camera. The ages of their faces and skin were then reversed digitally in post-production using a process called "digital skin grafting". The visual effects team worked from photos of Patrick Stewart and Ian McKellan when they were younger and they smoothed out the age lines and wrinkles in order to take 25 years off of each screen legend's face. In addition to reference photography, Lola's visual artists worked with a plastic surgeon, who helped Lola's team understand how the human face ages and kept them from making the fatal error of going too far with their touch-ups and making the actors look somewhat off.

Professor X Magneto DeAged

While the technology and the effects work that was done was cutting-edge at the time, the visual trickery of de-aging Patrick Stewart and Ian McKellan had to hold up on 40-foot movie screens, and later on home video. But even before the advent of high-definition screens, most audiences reacted negatively to seeing the venerable actors' visages so clearly warped. The younger Professor X and Magneto looked like wax figures of themselves and the effect was eerie to behold, rather than fully convincing.

Still, that didn't stop X-Men's producers from making a second attempt at de-aging Patrick Stewart when he cameoed as Professor X in 2009's X-Men Origins: Wolverine. The audience's reception to Stewart's encore appearance (as an even younger man since the film was set in 1981) didn't fare much better. After X-Men Origins: Wolverine, the X-Men movies rebooted, hiring younger actors to play nearly the entire cast and altering the timeline to suit their new plan for the franchise. In X-Men: Days of Future Past, the young Professor X played by James McAvoy even shared a scene with Patrick Stewart's elderly Charles.

X-Men: The Last Stand was the first major motion picture to feature the digital de-aging of its lead actors and, despite the negative reaction, Hollywood still chased the technology as a fad. The next few years saw other actors' faces have years digitally removed like Arnold Schwarzenegger in Terminator: Salvation, Brad Pitt in The Curious Case of Benjamin Button, and Jeff Bridges in Tron: Legacy. The success of these attempts varied. More recently, the digital de-aging technology introduced by X-Men: The Last Stand has improved, especially in Marvel Studios' films where, if it's not exactly seamless, it's certainly more visually palatable. Examples of these include Kurt Russell in Guardians of the Galaxy Vol. 2, Robert Downey Jr. in Captain America: Civil War, and Samuel L. Jackson in Captain Marvel.

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