WARNING: The following contains spoilers for The Adam Project, now streaming on Netflix.

Netflix's latest time travel adventure, The Adam Project, stars Ryan Reynolds as Adam, a pilot from 2050 who teams up with his younger self (Walker Scobell) to travel to 2018. Jennifer Garner and Mark Ruffalo play the parents of his younger self as the plot leaps from 2050 to 2022 before landing in 2018. The two Adams are pursued by Maya Sorian (Catherine Keener) from 2050, who comes face to face with her 2018 version halfway through the film. For the role of Keener's younger counterpart, the actor was de-aged with CGI. Unfortunately, the results are less than believable.

In order to portray the 32-year difference between future and past Maya, a visual effects process was used to modify the actor's features. CGI performances and de-aging has been slowly working their way into the mainstream. While some films like Ant-Man have been praised for turning back the casts' clocks, Keener's experience was not so flattering.

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Maya is the villain in The Adam Project

The filmmaking technique has been around since the mid-2000s, with X-Men: The Last Stand utilizing it to show a Charles Xavier (Patrick Stewart) and Magneto (Ian McKellan) forging the X-men in its early days. The Marvel Cinematic Universe continues to regularly create younger versions of veteran actors, such as Robert Downey Jr. playing a teenage Tony Stark in Captain America: Civil War. Studios have been particularly interested in resurrecting older franchises, such as Star Wars and, most recently, with a young Luke Skywalker's appearance in The Book of Boba Fett. Luke's flashback displays how far CGI acting could go when implemented properly, potentially even replacing actors.

Unfortunately, Keener's portrayal didn't go quite as well. For one thing, unlike the technology used in Gemini Man to create a Will Smith in his 20's, the younger Keener was not a 100-percent fully digital character. Instead, the visual effects team created a computer-generated, younger version of Keener's face and then replaced her real face with the synthetic animated version. Similar deep fakes are doctored with cutting-edge artificial intelligence that builds fake images by analyzing thousands of real ones. This facial mapping has had varying degrees of success.

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Real and CGI Keener

On the fringes of Hollywood, de-aging technology has gained momentum in releases over the last few years. Humans are naturally sensitive to faces, and research shows that a person will still recognize a face long after forgetting other details, like names. This is part of the reason that audiences often feel a sense of unease in response to a realistic face that still isn't quite real. This phenomenon is called the "Uncanny Valley" and is the reason that certain human-like digital portrayals are so jarring. The CGI becomes so distracting that it pulls viewers out of the movie and shifts focus from the plot. Even de-aging performances that have been highly praised, like Michael Douglas' Hank Pym in Ant-Man, has that digital sheen of the Uncanny Valley.

As time travel plotlines become more prevalent in the MCU's Phase Four, expect to continue seeing de-aged characters in branching realities. The technique can be considered as much of an art form as a digital process. Though it has great potential when used effectively, The Adam Project illustrates the pitfalls of getting it so wrong that it undermines an otherwise competent film.

To see the CGI mishap, The Adam Project is on Netflix now. 

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